Paddleducks
Other Marine Models => Live steam => Topic started by: bogstandard on May 15, 2007, 06:28:47 AM
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Please Note[/size]
This entire series of posts by John (bogstandard) and others, has now been recreated as a series of pdf files by Floyd (TFL45). They can be found in our "Downloads" section at the following link:
http://www.paddleducks.co.uk/forum/dlman.php?func=select_folder&folder_id=231
Our sincere thanks to John and Floyd (and all the others who contributed) for all their hard work!
Having carried out a full site poll, half way down a topic somewhere and having immense response, 1 really, I have decided to show how I build my engines from scratch (and junk), hopefully to inspire at least one person to have a go.
This opening post will be to try and convince you that making is not too difficult or overly expensive if you just have a few basic engineering tools.
Its always nice to have a fully equipped workshop, but even by buying a cheap lathe, Arc Eurotrade do one for just over £100 with maybe another £50 for some basic bits to go with it, can work wonders for your modelling, not just engineering, you can make most of your metal, wood and plastic fittings yourself.
A small vertical slide to fit the lathe will allow you to do not only basic milling but more complicated things as you get used to it, in fact what I do is use the machines to make more bits for the machines. An el cheapo drill press is a worthwhile investment, and can be obtained everywhere for just over £30.
For basic hand tools I use an engineers square, a little gizmo for finding the centre of roundish thingies, its actually called a centre square, again you can buy sets of these from somewhere like Chronos for just over £25 (this is great, spending someone elses money).
A selection of files, scriber, a good six inch rule, centre punch, hammer, the list goes on, but most people have the neccessary things already, you can buy purpose made deburring tools, but I use a stanley knife, by scraping the sharp edges at 45 deg, instant deburr, just change the blade every couple of months.
A flat surface and a sheet of very fine wet & dry takes care of lapping any faces, I used a piece of plate glass until recently, in fact it was the platen glass out of an old photcopier, (it only needs to be about 12" square), I had used it for about the last ten years, not just for lapping but anytime I needed a flat surface, just scrape the glue off before using it to lap. Unfortunately, glass, big lumps of metal and fumbling fingers don't mix.
Please bear in mind, with the machinery I have I can easily remove 5 or 6mm at a time, with a very small lathe or miller you will be lucky to remove one tenth of this, so you have to do a lot of small cuts. Usually the larger the machine the better, what will do a lot will also do a little, but not the other way round.
I am not saying that you could build an engine like this on the small lathe that I mentioned, but I would love you to prove me wrong. That was just to show that it needn't cost a fortune to start in engineering.
Now a few of my famous drawings showing the basic setup for calculating what is needed. This engine will not be a good looker by any stretch of the imagination, it looks very spindley, that is because again I have gone for the same bore and stroke 10X20 long stroke.
The next bit I submit will be even more long winded than this, because I want to mention a little about safety in a workshop environment. It needs to be done, and I promise, only the once. I have picked up more body parts from people alive and not so alive than I care to remember, so I can talk thru experience.
Digest this lot if you can, will do the next post either late tonight or early tomorrow. It will get better.
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I'm with you so far John, so you can't be explaining it that badly! ;)
You mentioned the cheap Arc lathe - Is it accurate enough to do what we need? I know cheap drill presses will drill any angle you want except 90 degrees! Though I have to admit that half the problem is probably caused by the drill bit itself wandering...
As I've said before, I'm not into working with metal (but I hope your article will change that), so what accessories will be needed for the basic lathe? Tools, chucks, etc etc.
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Hi Eddy,
If you read my post you should have noticed that I stated that this little lathe most probably wasn't up to the job for this article. The main problem is getting a vertical slide to fit something this small. That is the key to using a lathe to do milling, and also square drilling. Using the lathe chuck as though it was a milling chuck to hold the cutters or a drill chuck to hold drills so you could in fact get away with not needing a pedestal drill. The C2 or the C3 would be even better as good vertical slides can be obtained for these units, and they are more powerful and rigid.
I would suggest you let me get a bit further into the article before jumping in at the deep end and spending a lot of money. You might decide that machining isn't for you.
By the way, it pays to advertise to other members that you are looking for a lathe, they might have something suitable second hand and you usually get the extras included for a lot less than the cost of a new machine. All my machines were bought second hand.
John
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Don't worry John, I had no intention of leaping out of bed in the morning and buying a lathe! :)
I need a lot more convincing that I can handle things before I go flashing my chequebook around - My bank manager would never forgive me, or my wife for that matter!!
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Before I go any further, the most boring bits, but the most important. Ignore the warnings at your own peril!!! If you can't follow the basic rules, you shouldn't be anywhere near this post!!!!
From now on alcohol is banned from the workshop. Well thats got rid of 99% of the readers, we'll just carry on without them. In fact I'm most probably writing this post to myself.
Safety is a must, the eyes need careful protection, without them your modelling days are over, get a pair of safety glasses, AND USE THEM!!!!.
Machinery has no feelings, it will take your fingers off just as easily as it removes metal. Keep your bodily bits away until the machine has stopped. Long hair and shirt cuffs have an affinity for moving parts. Remember, don't become another piece of your latest project.
Metal that has been machined produces heat, and a lot of it. When I'm cutting some tough stuff it actually glows. Let it cool down before you touch it, and for goodness sake don't drop hot metal into water to cool it down, you might find that the metal has become hard as glass and you won't be able to do any more machining operations on it.
When metal has been machined, very sharp edges are produced, it will cost you a fortune in plasters. Don't put away a piece of metal until it has been properly deburred. In fact I deburr after every operation, if you don't, aside from the safety aspect will, if put against a datum face, will throw all your machining calculations out of the window.
It seems mundane, but getting splinters of metal in you skin can have drastic repercussions. Get a piece of brass embedded in your skin and leave it for a few days, the puss filled, weeping, gory open festering wound will wish you had got it out with a pair of tweezers as soon as it got in there. Remember there will be minute bits of metal everywhere, keep your hands away from it, sweep it up or better still get an old vacuum in there and suck it up as often as needed.
If you can add any more please do, I can't think for everyone, it is up to you to keep yourself safe and healthy, no-one else - YOU!!!. In fact in industry you can be prosecuted for having an accident, lose your fingers, get prosecuted, what a bummer. But you only do it the once.
Lecture over, it does get better, but it had to be said.
The Main reason you are reading this.
Project - To build a twin cylinder slide valve steam engine with the same bore and stroke as my previous oscillator, namely 10mm bore x 20mm stroke. This will allow parts designs from my previous engine to be used with this one. This will save a lot of time having to design new parts. All measurements are metric. Hopefully there will be no 'bit' measurements, I will try to keep everything to the nearest 1/2mm. I am also building in a few adjustable bits for those of us who are not quite as accurate.
Please be aware that I design and make as I go along, aided by a few sketches. If anyone wants to build one you will have to strip it down and measure it up, and give me a copy of the drawings.
Or else ask and I will post what workings sketches I have.
I will be building two engines in parallel so if you see two of everything don't worry, I am hopefully going to make one horizontal, and not by drinking alcohol.
Most of the raw materials for this build will come from the yard of many skips, or have been donated freebies from people that say "give it to that nutter John, save us having to take it to the tip". Little do they know about the cost of raw materials.
95% of my raw materials for building are not the correct size or shape, you have to go with an open mind and envisage what is in there trying to get out. I expect this engine excluding fasteners to cost me less than £10 in raw materials. Your local scrapman will become your best friend, slip him a couple of quid and he will be happy to hack old material into smaller bits, it will save hours in the workshop trying to cut it down yourself.
Throw no materials away. If while machining say a bit of brass and you cut off a 10mm long piece to get to size, don't throw that piece away, if you cut a bolt down, anything you cut off over say 6mm long, save it, great for making studs and joiners, saves time as well. Nothing is truly done for until it can no longer be used for anything else. It is people that don't follow these rules that get me all the raw materials from the scrapman.
The one thing that I do invest in is good quality fasteners, and I get them from here - http://microscrews.easywebstore.co.uk/
If it is not on the site just give them a call, only about 10% is shown on the site but they stock everything in stainless screwed fasteners, but only in metric I think, up to 4mm, and very reasonably priced as well.
By the way I have no affiliation to these suppliers, other than being a very satisfied customer
What I do is during the build I use any old crappy screws that I have lying around, and when the engine is up and running I put shiny new ones in.
Now to start (and hopefully finish)
Metal for the main block or 'How to hopefully recycle a useless bit of metal into a bit of metal with a use'
Picture 1 - The scrapmans moll, gently eased apart to show the tempting secrets within.
Picture 2 - With even more teasing further treasures are revealed.
Picture 3 - After an hours hard fumbling the sheer beauty is revealed, silky smooth, soft to the touch and a delight to fondle (I must stop reading the wifes girlie mags).
Picture 4 - Hacking off the outer skin to get a nice square block.
Not bad for a lump of scrap cast iron from the scrapyard that cost 30p (35mm cast iron bar, over £10 if bought from a metal supplier, over 90p per inch), will be able to get about 6 engine blocks (5p each) out of one sash weight and is most probably up to a hundred years old and you won't get much better seasoned material than that.
This has been a long haul post but it sets things into the correct frame of mind, just to reiterate, safety first and foremost, clean and deburred, get to know your friendly scrapman, don't be put off if you bodge it up, if it can be put right it was never wrong in the first place.
The next posts will be nowhere near as bad as this one.
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Lay back a little.
Metal doesn't just up and run away out of your chuck or vice (unless of course you didn't tighten up enough then it will chase you round the workshop), so take your time, the world won't end if you don't get the bit machined tonight, go and have a pint, be nice to the missus for a change. It is when you rush, get tired, fed up or whatever that accidents and mistakes happen, it will still be there in the morning. You are not in a production environment, unlike Sandy, who has to get things out on time otherwise his employees don't eat. Get to enjoy yourself, because if you don't enjoy it you shouldn't be doing it.
I don't use tolerances (this is a designed figure that you can work to, and if kept within the figures will ensure that the mating parts will fit together and carry out their designed function). Because these engines would be classed as prototypes, I make everything to fit individually. If you go slightly over or under on the bores, make the pistons to fit, the grim reaper won't call just because one bore is 0.02mm bigger than the other. So I try to keep to exact size, but I don't worry if not.
A few general notes for machining.
To get an idea of using a vertical slide on a lathe, when you see a picture of my milling setup, swing the picture thru 90 deg and imagine the cutter being in your lathe chuck and the vice as being the vice on your vertical slide, you can do everything I can do with my miller, maybe not as quickly, but as mentioned above, why rush.
Use a dial test indicator for setting the fixed jaw of your machine vice totally parallel and square to the cutting action of the cutter. This can be done without a DTI just by machining a piece of metal and measuring the results.
The fixed jaw of the vice now becomes your datum face, don't move it unless you really have to. After you have been doing any heavy cutting, check it again, just in case it has moved.
To get square out of round. Put material in vice, and face off the side. Then clean off the swarf, deburr both cut edges and remount into vice putting the now flat face against the datum jaw. Take a cut across the face, this will give you two sides square to each other, again clean and deburr.
The face you have just cut goes down into the vice with the same datum face that you used before against the fixed jaw. I set my piece onto parallels and tap the material onto that until it just grips the parallels, that way I know that everything will be square and parallel. But if the jaw is square to the base of the vice you should be ok.
Now machine the third side down to the required thickness, again, as usual, clean and deburr.
Put the first machined side down into the vice with one of the now machined and parallel sides against the fixed jaw, tap down the material and then cut the fourth side down to required thickness.
If all is well you should now have a piece of bar that has opposing faces parallel and square to adjoining faces.
If you can get this right everything else is almost easy.
Forgot to mention, a cheap digital vernier is a very good investment. Last one I bought was about £9 from Aldi.
Here is a website to give you a few basic instructions in metalworking, and explains things a lot easier than I can - http://www.nmri.go.jp/eng/khirata/metalwork/index_e.html
There is some pigeon english but most of it is understandable.
If there is anything at all that you don't understand, just go to Google and type in what you want, ie 'using a vertical slide' or 'how to use a boring bar in the lathe', most questions will give you all the info you require and just add the sites to your favorites for later reference.
The first picture shows a lot more than you think.
I have already faced one end of the cylinder block, now is the time to get it to the right dimension.
At the bottom left and right of the picture are two of my most useful bits on the lathe. The right hand one is the saddle clamp that locks the saddle solid, the left hand one is a saddle stop that I made for this lathe, it doesn't have to be this complicated but it can stop you ruining your lathe.
It stops the toolpost going too far and hitting the chuck, usually with irreparable damage. This is usually a fairly simple thing to make and you will wonder how you ever lived without it. The way I use it for facing is bring the saddle to it and lock the saddle, then I can use the top compound slide to give very fine cuts without having to worry about the saddle being pushed back by the pressure of the cut.
I am using my four jaw chuck to hold the material, the material doesn't have to be centralized when end facing, in fact with a little bit of ingenuity the whole block could have been machined in the four jaw.
I am a stickler for a good surface finish, and will spend hours lapping and polishing, so you will notice that I have used a bit of cut up drinks can (I prefer Pepsi Max, but almost any will do) between the jaws and the material, this is to protect the surface finish, chuck jaws are very hard and will mark most materials.
On the metal sticking out of the jaw, near to the cutting tool, you can just notice a felt tip mark near to the end. This allows me to rough cut up to that mark, leaving me about 1/2mm to go to length. Then I take a very fine facing cut (maybe 0.02mm , 0.001"). Then remove the piece from the chuck and measure the length. This will tell you how much you have left to come off to get to size. Remount in chuck with Pepsi Max, bring the tool to just touching the face then take your cuts, the last one being like before, very fine. You will find that you should have now a piece of material to the correct length.
The last bit in this picture is rather indistinct, that is the cutting tool itself. I started using one of these so called 'profile' tools about 5 years ago, and it is one of my most prized possessions in getting my own back against lumps of metal. They are obtainable from a lot of places but here is about the cheapest - http://www.rdgtools.co.uk/cgi-bin/sh000001.pl?REFPAGE=http%3a%2f%2frdgtools%2eco%2euk%2f&WD=profile&PN=INDEXABLE_LATHE_TOOLS%2ehtml%23a13086#a13086
Go to the bottom of the page and all will be explained. I bought five tips for it when originally purchased, I am just on the last one now. The beauty of these is that when the tip wears you just turn it a few degrees and you have a brand new cutting edge, and the surface finish is superb. About £3 a year running costs, not bad, and it is used daily for facing, reducing to size and of course a little bit of profiling.
The second pic is the blocks finished to size, blued up (this is not really necessary, but you don't have to scribe such a deep line to see it) and marked out for the job tomorrow, namely putting the big holes in.
Oh! and a little message for Eddy, here is the first wart (or pimple), the block was a bit tight to get out of the rough cast material and is in fact 0.15mm (0.006") too short on the height, but as I said, don't worry, all I will do is take the same measurement off the top of the piston and all will be right with the world.
John
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:D :)
Hi PD's,
John......Looks good so far, however, just a couple of additional tips for everyone.....when using a milling vice...
The face you have just cut goes down into the vice with the same datum face that you used before against the fixed jaw. I set my piece onto parallels and tap the material onto that until it just grips the parallels, that way I know that everything will be square and parallel. But if the jaw is square to the base of the vice you should be ok.
This will only work well providing your milling vice, or vertical slide vice, are of high quality...cheap vices are just not true enough....The inside (datum) face of the fixed jaw must be absolutely vertical (90 deg.) to the top face of the vice base, which in turn must be set truly parallel to the cutter. Ideally, the top face of the fixed jaw should also be absolutely parallel to the top face of the vice base (if not then use the top surface of the base as your second datum), but on anything but a high quality, or toolroom standard milling vice, it is highly unlikely that any of these requirements will be the case.
There are other methods, using an angle plate, parallels and suitable clamps, but I will leave it to John to enlarge on this for you, should he choose to do so...after all it is his article.
Oh! and a little message for Eddy, here is the first wart (or pimple), the block was a bit tight to get out of the rough cast material an is in fact 0.15mm (0.006") too short on the height, but as I said, don't worry, all I will do is take the same measurement off the top of the piston and all will be right with the world.
I would not be to concerned about 0.006" after all you have got, or should have, approx 0.031" clearance volume at each end of the bore...if you adjust the con-rod length (the big end or piston will I assume be screwed on) you can make this -0.003" at each end of the stroke...no worries.
BTW John, I hope you got the gist of my explanation on eccentric location/orientation...if not then let me know and I will try to explain it in a different way...sorry if it confused you, but it is an important detail.
As for standard direction of rotation....on single screw vessels the majority would have clockwise prop rotation when looking towards the bow from astern.
On twin, or multi screw vessels then Port side screws would turn counter-clockwise and Stb screws would turn clockwise...again looking from astern.
This is known as outward turning...in other words the topmost blades turn outwards, away from the rudder/s
Keep happy.
Regards to all.
Sandy. :sunglasses :computer :coffee
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Hi Sandy,
Many thanks for the comments, all duly noted.
Hopefully the article will not now be as long winded, I just wanted to get across the basic understanding of machining metal and what is involved, and put over how I cope with the odd situations.
The eccentric bit did confuse me because you switched ends half way thru. The way I see it now, is that when viewed from the output end (the end connected to the shaft), engine going in a clockwise direction, with the nearest piston in the fully upstroke position, the eccentric will be 90deg to the right, the rear piston is on its downstroke and its big end at 90deg to the right (the same position as the front eccentric) and its eccentric 90deg fwd of that at full bottom stroke, or should the rear piston be on its upstroke and it's eccentric be at the same position as the front pistons big end? Or doesn't it matter.
When I asked about direction of rotation of props, as far as I'm concerned, on the full size it is pointy bit at front, blunt bit at back, don't know whats underneath, can't see it unless I get wet. On models as far as I was aware, you always went for the safety factor and a single screw always went anticlockwise when viewed from the rear, so the shaft was screwing the prop on tighter (the same as the port side setup when viewing a twin output).
John
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Hi PD's & I do agree with the......quote by Sandy....
On twin, or multi screw vessels then Port side screws would turn counter-clockwise and Stb screws would turn clockwise...again looking from astern.
I think Sandy really means being astern & looking FWD :twisted:
.....however what happens in a triple engined vessel :?: ... from memory :shoot the above is true & also minimises cavitation...but the middle prop shaft in early British war ships & was in fact a shaft within a shaft complete with CONTRA rotating propellers
No one really liked this too much :ohno :nono :hammer & just prior to the GREAT WAR [WWI] triple engines vessels gave way to twin or quadruple engined vessels
Twin turbines were also used into one gearbox & propeller in merchant vessels
The US designed Doyle class FFG vessels [guided missile frigate] [4000 tonnes] [still servingi n the Australian Navy] have twin GE250 LM gas turbines through one gear box to one constant speed variable pitch propeller
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Now to get back on track.
I will sometimes mention a couple of words that need a bit of explaining and they are related. These are CONcentric and ECcentric.
Concentric means in our situation that the outside diameter has the same centre as the inside diameter, a good example is a well made washer.
Eccentric means the outer and inner diameters have different centres, like the holes on a button, stick it on a shaft and spin it and it wobbles up and down.
Found this site today - http://www.jjjtrain.com/vms/library.html
Almost everything you need to know about using the things and operations I use on the lathe and milling machine can be found here.
Be very careful though, if you are just starting out in machining the hours will fly by while surfing on this site. Vids and all sorts on here.
When drilling holes bigger than 2mm you should always if possible use a centre drill, if drilling large holes say of above 6mm, eg 10mm. Start with the centre drill, then use something like 4mm followed by one around 7mm, then 9mm and finish off with the 10mm.
You will find that the holes will be a lot more accurate than stuffing a 10mm straight in.
For sheet metal drilling I find that cone drills do a wonderful job, they don't snatch when breaking through.
The first picture shows centre drills and cone drills (another great buy from Aldi).
The second pic shows the steps I will use to drill the bores through the main block. I will finish off with a 10mm reamer, but if doing it on a lathe you can bore the holes or just drill them either mounted into a four jaw chuck or vertical slide, but you must make sure that you don't drill into the holding chuck or vice.
Two other things to note on this picture. The first is showing block sitting on parallels to allow drills to penetrate right thru without doing any damage. The other is that just behind the block is what is called a back stop, this allows me quickly to flip the block around and without having to remeasure, drill the second hole.
Backstops are also used on a lathe, I will point it out when I come to use one.
Third pic shows cylinders bored and reamed. The surface finish in the bore looks really grotty, but in real life they are like a mirror.
Work has now finished on the blocks for the time being, the next bit is to make and fit the pistons and rods.
John
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I still can't get over the fact that I'm actually managing to follow this without any problem!
I can see that I'm going to have to talk one of my club mates into letting me have a go on his lathe, then I can see if this sort of thing is really for me before parting with the hard earned!
However, should I decide that it is for me, and i go out on a spending spree - Where should I send the bill John? After all it will be your fault, so I think that's only fair ;)
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Hi Eddy,
Glad you can still understand it.
When people come round to my house to learn how to do things I usually get them to make something simple, like the picture below. There are dozens of people with one of these in their sailing jackets, it reminds them of the first thing they ever made on a lathe. Many of them now are craftsmen in their own right, not just machining but using metal for other things.
But be careful, using a file to profile needs to be done under supervision to show where not to put your digits.
Send the bill to Decoy, he seems to have a very good lifestyle that costs him very little, he can afford it.
John
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:D :D
Hi All,
John .....
The way I see it now, is that when viewed from the output end (the end connected to the shaft), engine going in a clockwise direction, with the nearest piston in the fully upstroke position, the eccentric will be 90deg to the right, the rear piston is on its downstroke and its big end at 90deg to the right (the same position as the front eccentric) and its eccentric 90deg fwd of that at full bottom stroke, or should the rear piston be on its upstroke and it's eccentric be at the same position as the front pistons big end? Or doesn't it matter.
Sounds like you have got the gist of this....from a model point of view it does not really matter...either is correct for running, however, on full size engines the NORM is for number 1 cylinder/crank to lead the number 2 crank by 90 degrees....so if you term your rearmost cylinder number 1 then when it is at TOP DEAD CENTRE the other one should be on it's up-stroke.
Just to add to the confussion :twisted: :twisted: :evil: ...He He....on real ships, number 1 cylinder is always nearest the bow (pointy bit to you). :music :hmmm :hmph
As for prop rotation...yes, on model ships/boats the general trend was to use anti-clockwise rotation on single shafts...this stems from the earlier times when IC engines were more the norm and these always run/ran anti clockwise.
On real ships, the prop is pretty well always keyed, or splined, to the shaft and the retaining locknut/s were always cross pinned or had keyed locktabs on them to prevent them unscrewing, sometimes they were threaded to be opposite the direction of rotation (left hand thread for clockwise rotation), or even both methods were used.
DEREK....yes I did mean ASTERN looking FWD... :thinking :shoot :hmmm why didn't I say that.....
I must admit, I have never seen a British capital ship with contra-rotating centre shaft props....but that does not mean they did not exist....and I can imagine the operational problems they would present.
Some of the WW2 German capital ships had 3 screws...TIRPITZ, BISMARK and SCHARNHORST...to name but 3....and their centre shaft followed normal practice as for single shaft ships...i.e they turned clockwise....same as the STB shaft....apparently this did give some problem with stearage when going full ahead on all shafts.....hence the reason for most British Naval ships to either have 2 or 4 shafts.
Interestingly though....a lot of earlier twin screw tugs had/have inward turning props since this does give better rudder authority at low speed.
Keep Happy.
Best regards.
Sandy. :twisted: :evil: :music :angel :computer :beer
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deleted :crash & reposted in the correct folder - Derek
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Sandy,
Thanks for the info again Sandy, I've got something right at last.
Did a few calculations last night, dog helped me, he's better at maths than I am. This is sure going to be an ugly engine, and because I am limited to height because of the size of raw material on the block it caused me a bit of concern, I would have liked about another 5mm on height but the dog and I have solved it all and still keeping to the 20mm stroke. A bit tight but definitely do-able. If its wrong the dog gets it.
Derek,
It was my birthday yesterday, and was treated to a pack of paper, no stopping me now, the only prob is, I don't know which way up the sheets are supposed to be, there are no markings on them.
John
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Hi PD's ....just to add to more confusion as Sandy said
on real ships, number 1 cylinder is always nearest the bow
well....not always.....the first 100,000 tonne bulk carrier - built [1960] as the Chelsea Bridge in Kobe [Japan] for the Ropner Shipping Company of Darlington [London] - first sailed as the Sig Silver for the Silver Line to Singapore & the chartered by our OZ :yeah GIANTS BHP :respect2 & then sailed as the BHP Iron Sirius :weight on the Headland to Kembla run for 25 years
Anyway :sorry ....the as built Chelsea Bridge has a 13 cylinder IHI built under licence - Sulzer engine & No 1 cylinder was next to the prop shaft turning gear :rant :great to see the engine fire up :boom :boom :boom from each of the 13 bleeders [:respect :respect :respect :respect2 = 13] :hehe
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Hi PD's - :hmmm ....not sure Sandy... how we should treat this new member 'Standard John of the Bog'
1) a one legged bandit :?:
2) a one armed machinist :?:
3) a most competent engineering artisan :respect2
'and' [ Bogstandard] I am glad to see a couple of your RELLOS found a REAM of A3 paper as there is none left in OZ :hehe
My humble vote would be 10/10 for point 3)....what do you think PD's?
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Just a word for Derek before I start. Thanks for the compliment. You said you didn't know how to take me.
Bogstandard means in rough terms a basic unrefined article. I am just that, no complications. If I don't know something I ask, if I know all about something I will help if someone else asks, if I'm not sure I try to keep my mouth shut.
I like good honest humour, the nod nod, wink wink type , nothing too deep, it hurts my brain too much. I don't expect praise or sympathy, but if it is given I acknowledge it. Now you know.
Back to the article.
I said last time that we had finished with the blocks for the moment.
I forgot that not all of you will have the means to get a good enough finish on the bore, they will most probably vary from a slightly dull surface, thru what looks like screwcutting to digging out the hole with a hammer and chisel.
If you can borrow a reamer, and your hole is still slightly undersize, use one, otherwise this is how I would get an acceptable finish.
You can go out and buy adjustable laps, but that costs a lot, just to get a couple of holes cleaned out, this isn't the totally correct way but it will be better than what you've got at the moment.
Start with the largest hole, stick the last drill you used through them and wiggle about side to side, the one with the biggest wiggle is the biggest hole.
Mark the largest hole with a felt tip. Now chuck up a piece of material to make the lap out of, have it sticking out of the chuck by 1.5 times the length of the hole plus 25mm (1"), I use hard nylon but aluminium or brass will also suffice, I get better results with the softer materials.
Carefully (no heavy cuts here, material sticking a long way out of chuck) and turn down the rod until it just pushes through the hole for a length of 1.5 times the length of hole (like the pic).
Now we need to spend a bit of money unless you are from the old school and have some in your garage. We need to buy some fine and coarse grinding paste, Halfords is about the cheapest at about £3 and you get a grinding stick with that as well. This quantity will last you for the rest of your life.
Dab a bit if the coarse stuff along the length of the lap, you don't need a lot. Get a piece of hardwood and with a rolling action in combination with turning the chuck by hand (you have stopped the lathe I hope) embed the surface of the lap with grinding paste, what you are doing is making a very accurate round file.
Select the lowest speed on your lathe and switch on. Keeping well away from the chuck feed the hole to be lapped onto the lap, get ready to let go on this initial feed in just in case it bind up and sticks. If all is well the lap will be turning (without you going round with it) in the hole. Now just gently move the block up and down the lap in a sort of rotary twisting motion. You need to keep the lap fully into the hole at all times.
Change the block position 90 deg around the lap every so often, eventually you will get the feel and a rhythm going.
Do this for a couple of minutes, stop machine and check the bore, it should have started to smooth out. Repeat as necessary, wipe off, recharge, turn the block around and come from the other end of the hole, until the rough stuff has gone, then wipe off coarse grinding paste with white spirits and recharge with fine. Repeat the operation.
You should after a while end up with a nice round, parallel bore showing slight scratch marks on the surface, these scratches will help the bedding in process as they retain oil while the pistons and bores are wearing against each other.
Clean off the grinding paste and turn down the lap to fit the smaller hole, and repeat the process again. When finished give the bores a very good clean out to get rid of any remaining grinding paste.
If you remember from before, the pistons are going to be made to fit the bores, so they don't need to be the same size.
Put the lap you have just made in a safe place, you might make something else where you can readjust the size and use it again.
I will do the pistons in the next article, it will give time for the batteries to recharge on my camera.
John
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Â
Hi PD's ....just to add to more confusion as Sandy said
on real ships, number 1 cylinder is always nearest the bow
Are you saying a paddle steamer is not a real steamer then? With a compound diagonal, triple expansion diagonal. or even an oscillating engine all three cylinders are equidistant from the bow
Â
Alistair
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Oh dear PD's... looks as though I have offended :oops another newer member as John posted.....
"Just a word for Derek before I start. Thanks for the compliment. You said you didn't know how to take me.........
I like good honest humour, the nod nod, wink wink type , nothing too deep, it hurts my brain too much. I don't expect praise or sympathy, but if it is given I acknowledge it. Now you know"
Bogstandard....in my defence :nono ...all I can say is that both the Sir Sandy of ArgYile & I as convict stock 20,000 miles distant have enjoyed great fun & banter over the past years along with many informative postings re STEAM to & from Sandy - I have many direct postings from other PD's :gather asking that we keep the show going........... :hehe
Your postings along with those from....typically.... our member 'Engineman' show how you guys can produce quality products and :kewl
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Hi Derek,
You haven't upset or offended me in any way, you just asked a question and I gave you a straight answer.
I find jovial banter very amusing and interesting, it is just finding the level where I could join in, it is a steep learning curve.
By the way, I have been got at before by professionals, so I have no problem with an amateur like yourself.
John
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:D :D :D :hehe :clap
Hi PD's,
Don't you just love it when a plan comes together.....
AlistairD......
Are you saying a paddle steamer is not a real steamer then? With a compound diagonal, triple expansion diagonal. or even an oscillating engine all three cylinders are equidistant from the bow
1st point......Not in the least Alistair...in fact I consider these the truest form of the term 'Steamer'...with in line steam driven ships a close second.
I deliberately chose not to include paddle engines in the argument......I felt this would really add to the confusion...and our John is already confused enough..... :respect :music :music
Whilst I was, of course, referring to in-line steam engines (rather than modern diesels or diesel/electrics) I do accept your point, however, even here what you say is not always the case.....some compound diagonal engines and oscillators for that matter, only have 2 cylinders, whilst others have 4 or more....and a triple expansion engine can have 4 cylinders and a 4 throw crank, but they are not commonplace I agree, especially in paddle vessels.
Regardless of these minor trivia though....a compound engine, however many cylinders it had, would normally have the 1st HIGH PRESSURE cylinder designated as number 1....and on an in-line arrangement this would be ,normally, closest to the boiler, which generally was ahead of the engines...however, I accept that there are exceptions even here.
As for DEREK and his 13 cylinder 'SUCK-SQUEEZE-BANG-BLOW SWISS CHEESE engine......well this just goes to show the Japs and the Europeans (excluding the UK) just have to be different/awkward and anyway these are not REAL engines....they just make a lot of noise and cause GLOBAL WARMING........How the hell do you expect to balance a 13 cylinder engine?.....no wonder ships suffer from heavy vibration these dddayys..... :hehe :hehe :oops :shhh
John.... :birthday ......I just LOL when I read the notes on your 'LAP' JPG sketch.....
'Having it sticking out to keep your hands safe'.... only works if your holding IT....and even then it's debatable!!!..... as for the other statements...I will leave them to the other PD's to ponder....but not when the other half is looking over yer shoulder.. :trophy :music :hehe
BTW....aks the dog which way the paper goes...he/she is bound to know....failing that, stick it in yer printer...don't ask me how, but these nearly always manage to work it out....if a sheet jams...you, and/or the printer know it is the wrong way round/up... :music :great :hehe :hehe
Keep Happy.
Sandy. :vacat :computer :angel :beer
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Hi Sandy,
Glad you liked a few of the explanations, I myself prefer the hands on and get it done approach rather than very technical terms, that's why I try to keep it slightly humorous, more enjoyable to read.
Marvelous these Japanese, being able to get the printer to recognize which is the right way up, but I've now got it sussed, if when I'm writing, the words come out upside down, the paper is the wrong way up. I haven't come across one yet, but I am sure I will one day.
No build sequence tonight, have been getting ahead a bit to make it a lot easier for me, top caps, stuffing glands, pistons and rods are now done, just need to get a few pics taken.
John
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Hi PD's....so Sandy asks..."How the hell do you expect to balance a 13 cylinder engine?"
Well lets go back 20 years to real units :music = shaft horse power...
so if 13 cylinders produced 50,000 SHP, each cylinder contributed 3846 SHP
but a modern 5 cylinder producing the same 50,000 SHP, each cylinder contributes 10000 shp
Therefore each :boom is near three times as great - critical engine speeds are those that :nono must not be maintained .... eg., like 22.5 to 23.0 RPM may be a :rant or 47.0 to 48.0 :rant & the engine room :computer just racks additional fuel to the engine when approaching these critical speeds
The only thing that critical engine speeds were good for was EXICITING the 20 year old wrist watch to keep it wound up :clap
Just to keep this from being :offtopic ...I think they has steam powered turbo chargers back then TOO :nah - only kiddin
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Hi All,
Sorry no posts recently but body bits wouldn't allow it.
Anyway, remember how I said in the first posts about scrap materials and turning nothing away.
A friend (yes I do have them) came at weekend and dropped this lot off (pic 1), they were moving to a new factory and were dumping old fixtures, so he thought of me and brought the metal and delrin off them, the bottom plate is about 15mm thick and 600mm square. So as I said, tell everyone what your hobby is, and sometimes christmas comes early.
The next pic is some hex bar offcuts from the scrapyard for less than £1 and turned down to 18mm for top caps and stuffing glands, there is enough here for 4 or 5 engines.
The last pic is a tip how I get all my holes to the same depth. This can be used anywhere you use a twist drill. Get a piece of tube just a bit bigger than the drill and slip it over the end, then adjust the position of the drill to the correct depth sticking out of the end, so when you get to the correct depth the tube is trapped between the drill chuck and the job so stopping the drill going any deeper.
Hopefully in a couple of days I will be able to post more pictures of where I am up to.
John
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Now we're starting to get onto the bits that really interest me John, so I'm eagerly awaiting your next posts....
Making the pistons, conrods, crank, etc etc.... We've done the basics, now we move onto the bits that baffle me totally! ;)
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Hi All,
There's no stopping me now, a pack of real paper and when I went to the bank I found a brand new pen, but some idiot had chained it to the counter, but being a prepared engineer I just happened to have a set of bolt cutters in my inside pocket.
So here is what Eddy has been waiting for. You never know what pleases some people!!
I am not going to go thru all the operations from now on, just tips when they are being machined, if you need to know how to do it just ask.
First pic shows top caps, packing (stuffing) glands and raw pistons (always make more than you need).
Pic 2 is the finished packing glands.
Pic 3 shows piston rods in blank pistons.
Pic 4 are the finished pistons with one having had an o-ring fitted.
First tip is for packing glands, make the screw in bit first, do not drill any holes thru them until you get to the stage where they can be screwed together with the main part still chucked in the lathe. Then screw them together and drill your hole thru them, this will keep them concentric. Keep them together in matched pairs.
For the top caps, you can have them as high as you want, on the picture there are two different top profiles.
I left the pistons until last, the sketch shows the finished size but make them initially to about 10.5mm diameter and 6mm long. The recess in the piston thread is to allow the thread to screw all the way in and sit against the shoulder on the shaft. Assemble the two together with loctite and leave for 24 hours. Your chuck must run very true for turning the piston OD., it has to be as concentric as possible. If this is not possible, ask and I will draw a sketch to show a very easy way to do it.
DO NOT remove the piston assembly from the chuck until it is finished. Turn the piston to length first (if you make the thread a little longer as well you will end up with a nice flat topped piston). The OD is turned down in minute cuts until it only just fits inside the cylinder (no floppy fits here, if so start again), stick a piece of very fine wet or dry paper or emery to a flat stick of wood and hold this against the side of the piston (no heavy pressure) until the piston just starts to slide nicely in the bore, you are looking for a clearance of about 0.02 - 0.03mm(0.001"-0.0015") if you can.
The groove is put in half way along (I make mine to fit a viton o-ring) and can be left empty so it uses collected oil to form the seal or it can be packed with either gland material (messy) or twisted up plumbers PTFE tape (fiddly) or like myself an o-ring.
Keep these assemblies matched to the bores.
IMPORTANT - ALL sharp edges on the piston need to be 'knocked' off with a file while still in the chuck, this will allow the oil to penetrate correctly for lubrication, but more importantly the sharp edges actually break down the oil preventing it from doing its job properly.
All holes that ANY shafts on the engine pass thru should have a small chamfer at each end, this is to allow oil penetration.
Please take note of the sketch with the block on it, this is nowhere near finished at the moment so you have to avoid certain areas if you want to start putting the end caps and packing glands on.
The rods on the pistons are not finished yet, I am still designing and making the middle part of the engine, so these will be finished off when all this area is proven to work.
The rest of the sketches are self explanatory.
John
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Okay, I'm confused John - Hey it doesn't take a lot!! ;)
From what I can see, the pistons are basically solid brass machined with a groove for the oil ring and a threaded hole in the bottom to take the conrod. But what about the little end bearing to allow the conrod to swing from side to side as the crank rotates? I don't see any sign of that...
I'm sure I'm missing something here, but clarification would be appreciated...
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Hi Eddy,
Because we are going to make a double acting engine (that means we have power on both up and down strokes) we cannot have a little end on the piston as we can't seal a swinging con rod, a car engine as we normally know it is only single acting, power on the down stroke only, so has a little end going thru a con rod to the crankshaft. But we are a lot more efficient and because of that we have to move the little end away from the piston and convert linear motion into rotary motion(crankshaft) so I have done a little sketch of how we are going to do it.
Also is a picture of a real life steam engine showing what I am on about. But if you look at this engine it is totally naff the way they counteract side thrust (you can see two bars sticking out of two of the columns), this is the area I am working on at the moment.
John
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AHA!! I knew there had to be a simple answer, thanks John.
Because I was thinking about a single acting engine I hadn't thought about the problems (and solutions) for a double acting engine.
But remember, I did say that I knew nothing about making a steam engine, so please be patient with me if I ask seemingly silly questions! :)
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Eddy,
There is no such thing as a stupid question.
Glad you now understand it, in fact it is a lot easier this way than with a little end in the piston. I know because I also build I.C. engines and they are a pig to machine the piston area, but not as bad as making the camshafts.
As I said before, I am trying to design this to be fairly simple to construct, with hopefully nothing that is not achievable by someone like yourself, that is why there will be no ballraces in this design and the crankshaft will be made out of about nine pieces all held together with bolts.
John
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bogstandard
I think you may find they are for OIL they have oil cups at the top of the columns. these are hollow and the bars are tubes just touching or not so oil is transferred to the rod. its the same as Martin howes and baylis used on some of there engines.
Peter
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Hi Crash,
I stand corrected, thanks for the info. Thats what happens when you look at a picture and assume. If you learn one new thing a day, by the end your mind will be full of information you can never use.
It now surprises me even more that they have no side thrust support, but maybe because it is such a short stroke engine they deemed it not neccessary.
John
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Away we go again.
I had to prove that this system would work before I could post, that is the reason for delay.
The crosshead is the link between the linear motion of the piston shaft and the rotary motion of the crankshaft/conrod. There are a lot of side loads imparted onto the piston and rod by the conrod so the crosshead transfers this side load to a more substantial bearing area than the bottom of the packing gland. I hope I explained that right, I am sure someone will let me know if I didn't.
The crosshead blocks that I am showing now are going to be the hardest part on the engine to make, if you can make these you will have no further problems making this engine.
First pic shows blocks prepared for machining, fully deburred and cleaned. All holes to be put thru this block should be done before any other work, this will make sure that they should be square and parallel.
Second pic shows two blocks fully machined, the raw one on the left and the partially dressed one on the right, you can use the raw version with no problems but I always think that the components should look the best they can.
Third pic is showing how the crossheads will fit onto the engine. The support plate and crosshead rods are not finished yet, these will be in the next post, plus a little bit of machining of the block to a stage where we can start to think about the crankshaft.
The sketch should be self explanatory.
John
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:D :D :bravo
Hi PD's,
John.....I am so pleased to see that you have fitted a proper crosshead arrangement...looks great and should work just fine.
When I looked at your initial sketch (1st post) and saw the arrangement this showed I was going to comment on it, however, since you were still in the design stage at that time I had a feeling you would re-consider the original method (which would not have given any support at all, at least not after the first few minutes of running)...well done.
:no1
Keep up the good work.
Best regards to all.
Sandy. :D :D :computer :beer
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Well, although very few members are asking any questions or making any comments, they must be interested judging by the number of times your photos and drawings have been downloaded John!
I can only assume the lack of comments mean that you are explaining things very clearly ;)
Keep it up John, I'm certainly following things with great interest....
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Well, although very few members are asking any questions or making any comments, they must be interested judging by the number of times your photos and drawings have been downloaded John!
I can only assume the lack of comments mean that you are explaining things very clearly ;)
Keep it up John, I'm certainly following things with great interest....
I think John is doing an excelent job of explaining :D :D :D
I check this form every morning to see if he has posted more ( also to see it Sandy has posted anything), sometimes I even check in the evening when the computer is free.
Keep up the good work :wink:
Regards,
Gerald :)
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Thanks for the encouragements lads, shame I can't get better photos.
You were right Sandy, after a couple of hours pondering I knew exactly what was required for the crossheads, the problem is keeping it easy enough for people to have a go, there are so many designs that could have been used but this was one of the simpler ones, and keeping within the format of no complicated decimal places is another restriction. Also for the few who cannot be as accurate there has to be an inbuilt element to allow for 'tweaking' to get the parts to run correctly.
Hopefully another thrilling installment tonight.
I nearly didn't make it yesterday, when milling I have to sit down, and when I swivelled round to pick up my mic the chair broke dropping me rather heavily onto the floor, but after an hours pampering and sympathy from the better half I was up and running again, managed to get 32 x 2mm holes drilled and tapped before the aches and pains took over.
John
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The first thing to do is to get a few more holes into the main block.
If you check the first sketch it shows the positions of the four ports that are going to be feeding steam to the top and bottom of the pistons. It is fairly deep drilling but if you take it steady there should be no problems.
Do NOT deburr the ends of the holes on these, we need them nice and flush.
Top caps and gland seals. I have taken a picture of how to use a square to get your holes looking neat. Once you have them in the right position dab a couple of drops of superglue around the edges and let it go off for a bit. Cunning don't you think, and the glue just scrapes off easily afterwards.
Anyway, get the drill that you used for drilling the holes in the caps and just spot thru to give you a dimple for your centre drill to pick up on. Tap the caps off and just centre drill all the holes, followed by either a 1.5 or 1.6mm drill to a depth of about 8mm. for the top caps it is not too important, but for the glands I mark the gland and the block to keep them as matched sets.
You should now have all the holes in fairly good register. Now 'just' tap them all out with a 2mm tap (or if you are using BA or similar use whatever drill and tap that is required). Forgot to mention, do one end of the bore first then clean off and proceed to the other end, otherwise you will find it wobbling all over the place as you try to drill. For tapping small sizes I always use a hand tapping fixture that I made using an old surface plate (this is what I take most of my pictures on), but Arc Eurotrade sell them for about £35+, I have very rarely broken a small tap when using one of these as you have a lot more 'feel'.
Another tip here, you will notice in the pic a weird set of pliers, go to the pound shop or market and buy a couple of cheap pairs of electricians pliers, hold the jaws slightly apart with a bit of metal shim (pepsi max) and drill thru holes, any size you want to hold, I have two pairs one metric up to 6mm and one imperial up to 1/4", you will find these are indispensable when you hold shafts when tightening (no marks like mole grips leave), and great when grinding bolts to length.
Fit the glands to the block, and make the support plate (don't worry if your plate isn't exactly the right thickness, but don't go too thin, as we can fix that when we come to fit the main block to the crankshaft area). Yet another of my grotty sketches, and spoiling you lot as well, I've used a ruler this time, again it is self explanatory except that on the photo it shows more cutouts, this is me again, tidying things up and reducing weight, not neccessarily needed, you can do it if you want to. You will also notice I have done a bit of rough engine turning on the plate, this is a very easy way to cover up all the marks and scratches from the plate being kicked around the scrapmans floor, if you want to polish it go ahead, it will be your engine.
The large holes in the plate are to go around the glands, if you are not up to doing these, no problem. As long as the six holdown bolts for the plate are there you can make these square, triangle, oval or any other shape that takes your fancy. The reason I did it this way was to accurately locate the mounting plate around the glands while the holes were spotted thru, the plate has to be VERY square to the block for the crosshead to function properly. But again things can be 'made' to work if not quite there, how to do this comes later, don't need to worry about that yet.
Drill and tap the block for the six mounting screws (B on the sketch) 2.5mm by 10 deep, and bolt the plate on.
Now you have got the holes drilled and tapped we can give you a bit of 'tweaking' power.
On the glands only, reduce the 18mm O.D. by 0.1mm and the same amount on the spigot that fits into the bore. You might find now that the piston is a lot freer in the bore and if not totally concentric with the shaft will allow you to spin it a full 360deg. rather than binding up. Tighten up when all is running free. If you still can't get a full rotation on the piston, just stick the piston assembly back in the lathe and dress it again with emery cloth on a stick (as previously described) until you get the desired result.
We will get back to the block later, after we have finished the crankshaft, as I have to design the cams for the piston valve and the valve area itself towards the end of the build (God, I hope this engine works, I will have people chasing me round with axes if it doesn't), think positive, how hard can it be, all will come right in the end.
Hopefully next we will be getting the crossheads and pistons into unison, something that moves that you can play with and really impresses the neighbours (I'm talking about the engine bits), plus a start on the crankshaft area.
Having a couple of days at the sewerside, sorry seaside, with the grandson, so no post for the next few days, but hopefully back with a vengance after that.
John
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Just to clarify things John, is it the top caps and gland seals that you are temporarily holding in place with superglue?
You briefly mention doing engine turning.... How do you go about that exactly?
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:D :D
Hi All,
Coming on a treat John......only one issue....
....I've used a ruler this time, again it is self explanatory
You may/will need to spell this out in 1 sylible terms for our Derek..... especially if it's got numbers on it......:oops :hehe :hehe :music
Keep Happy.
Best regards.
Sandy. :computer :beer
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You've caught me just in time, getting ready for a bit of relaxation.
Hi Eddy, yes it is the top caps and glands that you stick down while you spot thru with a drill.
What I call engine turning, I use to cover up badly scratched bits that would need a lot of cleaning and polishing otherwise. But it can also be used for decorative effect.
All I use is a piece of dowel or soft metal with the end faced up in the lathe. Then it is mounted into the chuck of your pedestal drill, with the faced end downwards towards the job, put a bit of grinding paste on the faced end and go thru the motions of drilling the plate but in fact all it is doing is scratching a pretty circle. Move the plate along a bit and repeat, move the plate along a bit and repeat, move the plate along a bit and repeat, move the plate along a bit and repeat, move the plate along a bit and repeat, move the plate along a bit and repeat, move the plate along a bit and repeat, move the plate along a bit and repeat and so on until you have a pattern that takes your fancy, if you don't like the pattern, start at the beginning and go over the old pattern. You don't have to use grinding paste, metal polish, a bit of emery stuck on the end, toothpaste, in fact any abrasive material will do, and they all give variation to the depth of pattern. If you mount the job into a cross vice and take your time very regular patterns can be produced using this method.
My ex friends (now no longer with us) son works for Bentley motors and suggested this for their dashboard, it was taken up and is now standard fitting, but they black anodize afterwards. So if it's good enough for them........
Have a go and play about, soon everything in your boat will be engine turned. I made an oscillator for a model shop owner in Frankfurt, Germany for his collection to put on display in his shop, I did 4mm engine turning on every flat surface of the engine, using metal polish, the result looked spectacular.
I forgot to mention in the last article that the plate holdown holes could in fact be drilled straight into the block using the dimensions on the drawing rather than being spotted thru.
Back soon
John
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Hi PD's... & what some call "What I call engine turning"....others of proud Convict :gather nature were taught :crash this process as "Radial Burnishing of Metals" during our elementary mechanical training [which also included the 'BOLT cutters in the coat trick'] :hehe
I must agree, a limited surface of radial burnished metal does add an asthetic dimension :kewl which is better than scratches & dents... :crash
A note from my relo on the first fleet to OZ suggested that in 200 years or so some WIZARD :angel from OZ may invent a clear epoxy spray for such work so the process of polishing did not ruin the beautiful radial burnished metal surface :sorry :music
Oh BTW John....in OZ we use a mixture of 1/4 tea spoon of IRON ore + 25 ml of VB :beer + 100 gms of goats milk butter to make our own lapping paste :nah
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Hi all,
Fairly refreshed and glad to be back.
For those who would like a bit more info on engine turning, the first link is to a chap who makes a living at it, the second link is another type using what is called a Rose Engine, mainly used by watchmakers and jewellers.
http://www.cs.ucr.edu/~eamonn/et/et.htm
http://www.rgmwatches.com/engine.html
Derek, my formula is a secret, but we use cow dung instead of aussie goats milk butter, it smells better.
Back to the build, very little tonight, just a sketch showing the crosshead support rods and the now finished to size piston rod, plus how the top of the piston and steam inlet hole should look when setting up.
The pic shows my two engines with the area totally assembled.
Building up - As you assemble put a spot of oil on all parts. Screw out the gland compression screw by about 1mm, then insert the piston and rod through. Now slacken off the holding screws on the gland and position the gland on the bottom of the block until you can get a free full up/down movement and a full 360 deg. rotation of the piston and rod without it binding, once you have this tighten up the screws and recheck.
Screw on a 3mm nut onto the end of the piston rod and follow it up with a crosshead, screw all the way on. Move the crosshead to a clear area of plate and push it down all the way, the piston should be near the top of the bore. Lift the crosshead 1mm away from the plate and adjust the screwed in piston rod until the inlet hole at the top of the bore is only just totally uncovered by the top of the piston (see sketch), tighten up the locknut (not too tight, they have a tendency to to deform things if too tight).
Put one of the crosshead support rods thru the crosshead and screw it to the plate, if the crosshead has locked up slacken off and adjust until it frees off, then put the other rod thru and do the same. All mine locked up totally solid, so I gave myself a bit of movement by opening out the support rod screw holes to 2.7mm. Do NOT on any account touch the piston rod/gland/crosshead assembly, all adjustment is done on the two rods. It took me about an hour to do the first one and about 10mins each for the others.
All adjustments on the rods should be with the crosshead against the plate, it is just a matter of slacken off, turn rod slightly and retighten, try again. It also helps if after tightening to tap the blocks with a plastic screwdriver handle, nothing heavier unless you get really piddled off then a 7lb lump hammer comes into its own.
What you want to end up with is the piston being able to go thru its full travel without jamming up, slight finger pressure is great but if you have to push a bit it should be ok, we will use the engine itself when completed to sort itself out. I check by putting the piston at the top of its stroke, block the end of the cylinder with my finger and put a bit of air into the steam port on the side, keep your fingers away from the crosshead, it comes out with a bit of force.
After all this by the way, it has to be stripped down at the end to finally seal, but you will have a lot more experience by then and you will be able to do it in minutes.
By the way, an engine doesn't come to life until you have some of your own blood on it, try not to make it too much.
The next time I will be starting on the bottom half of the engine. Some of the bits are common to my last engine so it should progress a little quicker. Going now to my scrapman box to see what I have to work with.
John
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This is just on one subject tonight, It has taken me all day almost non stop to get these made.
There is as usual one of my quickie sketches.
Next pic are the raw blocks and the piece of metal they were hacked out of is in the background.
You will notice that the blocks have colours on them, the green is on the datum face and red on the opposite end to aid identification. This datum face is critical as will be explained later.
The next pic shows a row of blocks all in perfect register with regard to height. Pressure can be put across all the blocks and the shaft still rotates.
The picture of the lathe setup is showing the last operation on the blocks.
The last pic is showing all ops carried out on the blocks.
Now the long winded explanations.
The blocks should be made to the sizes stated, in fact the 10mm size could be made maybe 0.2mm undersize, it will allow a bit more freedom when we get to the big end area.
It will require four for this engine, I usually make an extra one or two just in case of mistakes, but this time I ended up with all perfect.
The reason for the coloured marking is now explained. Mark a datum face on every block on a 20mm x 10mm face, this is the face that is always against the fixed jaw of your vice when boring the 5mm thru hole. Everything else on the bottom end of the engine can be tweaked but not the fixed height of the hole unless you have a long 5mm reamer to line ream.
After every block is bored the whole vice area has to be cleaned, a small amount of swarf can throw the height of the hole out completely. I use back stops to aid positioning, thus I just have to position a new block and tighten the vice, no slide movements at all during the hole boring procedure.
If You are lucky you should be able to put a 5mm rod thru all blocks, put them down on a flat surface and apply pressure to the tops of all blocks, the rod should still be able to turn, if not one or more hole heights are incorrect and will have to be sorted before going any further, maybe by putting shims under the low hole blocks, do NOT remove metal from the others to get them lower.
Assuming all is ok we can carry on. Instead of external oil cups we are going to build them into the blocks, just drill thru where shown with a 1.5mm drill then follow it down with a 4mm drill for a depth of 3mm including the drill tip, spin the drill or reamer in your fingers you used to bore the hole in the crankshaft hole to deburr the oil hole, job done.
Turn block over and drill and tap 2.5mm the two holes on the datum face. Don't forget to put a small chamfer on these holes otherwise it will throw the height of your crankshaft hole out.
The last job on each block is to machine a small boss on each side. The reason for this boss is to reduce friction, because we are not fitting bearings into this engine, if the crankweb comes into full face contact with the block there would be a lot of friction produced, by using this little boss friction is reduced to a minimum.
Turning the boss. Get one 5mm bolt and cut the head off. Put cut off bolt into chuck with threads sticking out and tighten up really well. Now just put a block onto the threads and put a nut on and trap the block between the chuck jaws and the nut (look at lathe setup pic). Bring the lathe tool into contact with the rotating block face until it just touches. Stop the machine and lock the saddle if you can. Wind tool off block and using the topslide put on a cut of 0.15mm (0.006"), now start machine and cut across the face until it nearly gets to the nut (not critical), now wind out on cross slide and stop machine, turn block around so face just machined is against the chuck. Repeat the process on the other end. Do each block the same, the bosses might not be concentric with the bored hole but it does not matter.
Blocks made, deburr and smile, the critical bit is over.
Next will be baseplate and hopefully crankshaft.
John
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Before we start with the next thrilling installment, I made a mistake on the last post about the height of the bearing blocks and if you had any that were low you should shim them up. I had forgotten that we have adjustment to cater for this later on, so you can in fact reduce the height of the others to match. The easiest way is to put a rod thru them all and flat down using abrasive paper and a flat plate, no not dinner or side but something like a piece of glass.
Tonights offering is the baseplate. I am making mine out of 2mm brass, the same as the top plate, and using standups underneath to give clearance for the crankwebs. This method is a bit flimsy but it is designed to bolt to the boiler and engine support plate, so making it totally rigid. If you wanted a free standing engine you could use thick aluminium plate but a minimum of 12mm thick, you would have to counterbore underneath to set all the mounting screws in but it should not be a problem.
First off is a sketch, on here just follow the measurements to make the plate, but please be aware of the datum lines, one is the longtitudinal (thats a big word for a monday night) centre line, the other is one of the short sides. All measurements are from these two datums.
All the photos should be self explanatory, except for the one simulating an engine build up. The rods on this are not the right length and will in fact be a bit longer, the feet under the plate are approx what it will be like, they have to raise the plate because that cranks have to protrude thru the plate.
Also on the third pic of the finished plate you will notice the corners of the cutouts are rounded off. I used a 4.5mm cutter but I wouldn't go any larger than 5mm otherwise the crankwebs might foul on the corners.
Next will be the crankshaft.
John
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Another superb installment John, and I'm still feeling that this isn't totally beyond my capabilities which is amazing! :)
I realise this is jumping ahead a great deal, but I do hope you'll continue on to include making a boiler, burner, condensor etc etc, so that we eventually end up with a complete steamplant? And maybe even consider a short discussion on any modifications that would be needed to convert the engine to a horizontal/diagonal type more in keeping with the majority of paddlers?
I've already had words with one of my clubmates so I can get some practice in on his lathe later in the year - We both have too many other things on right now do do anything immediately, but he's happy to let me have a go and guide me through the basics.... If that goes well, I can see the purchase of a second-hand lathe could well be on the cards for next year damn you! ;)
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Hi Eddy,
With regards to making a boiler, I have built a few in my time, even gas fired ones using the same technology as they use nowadays, but to cut a long story short I don't fancy starting to make boilers again when there are perfectly good boilers to be had at very reasonable prices from the professionals. Besides the fact I have seen some boilers that people have tried to make in their garden sheds using small gas plumbers blowlamps, I am not saying that it can't be done, and again I have seen some great ones, but the thought of me giving free reign to someone to attempt to make a boiler to my specifications, I'm very sorry but NO, I just couldn't bear the thought if someone was injured. Leave it to the professionals. I saw a chap once pressure testing the thing he called a boiler, he had it weighted down with a brick in a bucket of water and it was directly connected to his compressor, he was standing over it to see if there were any bubbles, you couldn't see my a*** for dust.
I am already looking at turning one of my engines into a horizontal, but it looks like it will be a bit more difficult than my oscillators, by the way I have to stop this build this weekend for a while, a gentleman has commissioned me to convert one of my engines into a horizontal for him, so I expect to restart early next week.
The main problem is the pipework, if I can get it compact enough I will give it a go. I don't think it will look very pretty, in fact downright ugly (just like the ones we are building here), but as I said at the start of this project, it is a design and make as I go along and I don't even consider esthetics, just make it simple and make it work, that even a beginner has a chance of completing. In fact it might be easier to design a purpose made horizontal, I will get some fag packets together and see what materializes.
With regards to a lathe, don't blame me, it was your suggestion in the first place. But for the cost of a small lathe and all the related bits is less than the cost of a moderate kit, it does open up a whole new world in the term 'modelling'.
John
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Tonights offering is all to do with the crankshaft area.
As usual there is a sketch for items to be made. The flywheel can be made as is or like I have done, put a recess in each side for cosmetic effect.
There are two drawings for the crankwebs, one semi balanced and the other a lot easier to make but not as nice cosmetically.
Pic one is showing how I lap in the bearing blocks. The rod is about 1 1/2 times the length of the bedplate and is the same material as will be used for the crankshaft centre rods, 5mm stainless or silver steel. At this stage the rod is very tight in the bearings. Put a little bit of metal polish or T-Cut in the lubricator pots, hold onto the plate and turn the battery powered drill/screwdriver on (I wouldn't recommend an electric drill, too fast unless you have speed control).
Hold tight to the plate in the beginning, it will try to spin round with the shaft, if too tight hold plate in a vice until the parts start to rotate a bit freer.
As it starts to free off, slide the plate and blocks up and down the shaft. After about 10 minutes of this you should find that the parts now move a lot freer. Clean off everything very well to get rid of all abrasive. Put some 3 in 1 oil or something as thin into the oil cups and spin the shaft, it should be nice and smooth. This shafting can be used for making the crankshaft rods, we have only taken microns off the OD.
Pic two is showing the rough blanks for cranks and flywheel and the scrapmans bar end that they came from.
Three is the blanks ready for precision drilling. The distance between the crankpin (5mm) and the big end pin (4mm) is critical and should be drilled using machine cross slide for the setting. The distance isn't critical, but they must ALL be the same.
Pic four shows what you should be aiming for, all ten of my discs slide easily onto the two different diameter rods, I must stress again THEY HAVE TO BE EXACT for this design crankshaft to work. The 2.5mm hole is not critical.
Also shown is what the finished semi balanced crankweb will be like. I should get them finished tomorrow.
Next hopefully is building up the crankshaft.
John
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hmmm... The first bit that has really worried me!
It looks like a fraction off with the drilling and either it won't fit together at all, or it will lock up as tight as a ducks whatsit!
Would it be better to drill all the holes in one solid block and then part it off into the seperate bits that are needed?
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At last, now we are getting there, you are starting to think like a model engineer. Problem solving is about 90% of the job when tackling something like this. It should be "How am I going to make it?" for every part that is not self explanatory. This is the satisfaction I get from making things out of all sorts of materials.
The only problem with your idea is getting the hole to drill perfectly straight when going so deep. Its about time people started to worry about making things shown here and ask the question, I have already done it so I can supply the answer, if you don't have the same machinery that I have, I can come up with another way for it to be done. There are lots of ways to solve most of the problems. Making a little jig is the usual way to do it.
The easy way is to make a jig out of steel (see attached sketch) and follow the instructions.
The way I do it is to set stops for the part to sit against in the vice, and after the first one as long as you do not move any machine settings it is just a matter of dropping the next piece in and drill and so on, I drilled all ten of mine after the initial setup in less than 15 minutes (I deburred each part after it was drilled, and blew away the swarf before the next one). The small hole is drilled later, that isn't critical, its only a pivot point for the metal to distort around.
I think from now on for difficult bits I will take a photo of my setup, but most of the difficult bits have now been done. Ah well, we'll get it right one day.
By the way Eddy, I hope I didn't offend you in any way over my rather terse comments about boiler building, it was just my views being expressed, it was nothing personal.
John
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At last, now we are getting there, you are starting to think like a model engineer. Problem solving is about 90% of the job when tackling something like this. It should be "How am I going to make it?" for every part that is not self explanatory. This is the satisfaction I get from making things out of all sorts of materials.
The only problem with your idea is getting the hole to drill perfectly straight when going so deep.
Believe it or not, I did immediately think of the problem of drilling so deep that the drill bit wandered, but it seemed like a possible solution.... Obviously your jig idea removes that problem.
I have to admit that it's the first time I've ever been told that I'm "Thinking like an engineer"! - That has just made my day! :)
By the way Eddy, I hope I didn't offend you in any way over my rather terse comments about boiler building, it was just my views being expressed, it was nothing personal.
John
Not in the slightest John - I fully understand your reasoning. I still feel it's a shame that we won't end up with a totally self-made steamplant, rather than just an engine, but I can still accept the technicalities (sp?) and why you feel that way.
I'll just have to contact Sandy when the time comes and spend some of my hard earned with him :(
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I went into the workshop this morning hoping to finish off the crankwebs and shafts, then a thought occurred to me, I hadn't even considered one of the major parts - THE DREADED ECCENTRIC - no, not me, but a little thing thats puts the dread into making small steam engines, and they are so simple to produce if gone thru logically. I have already done a bit of preliminary design work on the piston valve block so I know what lift is required.
Study the sketch, a bit offputting isn't it?
We are going to split it down into easy parts.
Start by turning the bar down to 18mm and face the end, put the 4mm wide groove into it, 1mm from the end. Measure 10.5mm from the faced end and part off at this point. Repeat the procedure. Remount the cutoff piece into the chuck with the groove inside the jaws, Face up until you have a length of 10mm (no longer, if anything go slightly under), you should now have what is shown on pic 1.
There are a few different ways to put the eccentric hole thru, but this one is bob on accurate. If you refer to pic 2 it shows my bits of metal mounted in a chuck of a rotary table and a DTI running around the edge. I use this setup because it is easier for me with my slight infirmity. As I said before, If you are doing this with a vertical slide, imagine the DTI in your lathe chuck and the part to be drilled in your vertical slide vice. Basically what you have to do is centralize the workpiece to the chuck.
Once this is done, just offset the workpiece by 3mm using your crosslide or vertical slide, put the drill in the lathe chuck and drill thru. Eccentric conquered. You should end up with bits like shown in pic 3, while I had the workpiece set up I took the opportunity to mark the end with the groove to help with setting up the engine.
Next, remember a few posts back where we set up in the lathe for putting on the anti friction bosses on the crankshaft blocks. Well the next operation is almost the same but a little more precise.
Take a piece of 5mm rod and mount it in the lathe and drill and tap the end 3mm. Move the rod back in the chuck until about 8mm is protruding and give it a good tighten. Slip on the eccentric with the groove towards the chuck and screw in a screw and washer to grip the part against the chuck jaws, see picture 4. By the way the 4 jaw chuck I am using here is not a 4 jaw independent but a 4 jaw self centring, same as your 3 jaw but with four, I find them a lot more accurate and more versatile.
Now take very fine cuts (max 0.3mm) for a distance of 4mm along the workpiece. Keep taking fine cuts until a boss diameter of 12mm is reached (not critical).
Take off eccentric and drill and tap the 3mm hole at the position as marked on the sketch, it can be anywhere around the boss.
You should now have eccentrics that look like the ones in pic 5 (mine have yet to be drilled and tapped).
Now wasn't that easy campers, next week we will be making a 24 lobe camshaft for an aircraft engine.
Thats it now until next week, I have some other work to do.
John
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Hi there John, thanks to you (on cnc forum),I resolved the problem of drilling a series of tiny holes ,using tiny (0.9mm) centre drills to spot first, worked a treat!. I got them from some polish guys who set up a market stall in a layby near my house here near Florence,I think they must halfinch the stuff from where they work in Poland! ,I also got a nice 5" 4 jaw ind. chuck new!,and 10 bars,8-10 mm round and square of good hss, 10 of the centre drills all for 50 euros! (about £30),by the way the chuck fitted straight on the boss on my lathe!.If you look on the new people section under engines on this forum I put up a photo of an engine I'm working on ,you'll see that the heads on the cylinders have 4 holes around them ,I did them ,after some thought, hole by hole on the mill ,but as Eddy suggested(but some time ago) all from the same piece,and then parted them off, as they are only 4mm or so thick I thought it would be ok ,but the drill did wander a touch on one ,luckily not enough to be seen with the pan head allen screw in it, but still annoying!.I have an idea for a v twin overhead valve engine I'd like to make,maybe I'll start a thread!...thanks and well done on your engine and very well explained!.I'm of the fag packet school like you (sometimes I don't even do a sketch! ,I'm too lazy!)I think these forums are great ! lets keep up the good work!...P.S. I'm with you on the fact that dogs can be a great help with these things sometimes ,they have a more relaxed point of veiw!....Giles
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Hi Giles,
Nice looking engine you are making there. I like the look of what the chap who does the plans has to offer, they are very artistic and modern looking. Might even have a go at one myself, a bit of light relief.
Even though this is not an engineering site, I find the people on here very knowledgeable and willing to help as much as they can, When I was looking at making this engine, I didn't fully understand the working geometry of the piston valve setup, but I asked the question and everything was explained very easily to me.
I know what you mean about roadside markets on the continent, I was driving thru Czechoslovakia a couple of years ago and there was a huge market at the side of a motorway turnoff, all makeshift like a shanty town, but you could get almost anything there, from a box of matches to a car engine, all brand new (I don't suppose there is much call for second hand matches, but you never know).
Keep up the good work and if you need anything, just ask, and remember we all cannot know everything, and there is no such thing as a silly question.
John
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Just out of interest which is the cnc forum you look on? Peter
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Hi Crash,
Even though I don't have CNC I found this site very helpful, v-e-e-e-ry technical in places. This is the one we were talking about.
http://www.cnczone.com/
John
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Thanks for that I have regested , seem to be a bit USA based ,but looks good. Peter
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Here is the reason for not posting the last few days.
A gentleman commissioned me to convert one of my uprights to a paddle engine.
Rather than rushing as I did the prototype, plus no need to convert back, by changing the position of the large gear bearing I was able to reduce the overall length of the bedplate by 20mm, giving a much more aesthetically pleasing engine.
Will be posting again on the piston valve maybe tomorrow or definite thursday.
John
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Tonights little offering is showing how to finish off the crankwebs, showing an easy way to machine the webs to size all in one go rather than separately.
First off a bit of milling criteria. Due to the normal types of machines, either lathes with a vertical slide or the general purpose milling machines (like mine and 99% of most people) you should NOT be doing any CLIMB MILLING unless you really want a new facial feature that looks decidedly like the job you have in your vice, and maybe the cutter as well.
You only do a cut one way, CUT, rewind back, put on new feed, CUT, slower but safer.
DOWN CUT or CLIMB MILLING should only be done by experts with the correct type of machinery, and this is one of the main reasons amateurs like ourselves (and I have done it) have ruined a perfectly good job because we put the cut on the wrong way.
You should only be doing CONVENTIONAL or UP CUT Milling. The first pic is a copy out of a machine manual that explains it very well, if you can't understand it, just ask.
The second pic shows all my crankwebs mounted in the vice. The cunning bit is the bits of brass you see there. We are going to use the accurately drilled holes to our advantage.
There are two different sizes, 5mm and 4mm. If we get the centres at the same height it will be just an easy machining job. To do this by the way, when your vice jaws are tightened together they should be in line with each other and also the tops of the jaws need to run parallel with the end of the cutter in your chuck. Whenever I invest in a new vice the first thing I do is grind the tops of the jaws parallel to the base, for just this sort of job.
If we subtract 4 from 5 this gives us 1, half it and we get 0.5mm. Now search high and low to get some material to use as shims, anything solid, metal, plasticard, even shim stock if need be, of 0.5mm thick.
Put the job into the vice like shown on the pic and slip the shims under either side of the 4mm rod, push down and tighten the jaws. This now ensures that all machining is now parallel to the hole centres. This trick can be used anywhere you want to machine parallel to two hole centres.
You will also notice I am using a back stop again, this allows me to reposition the job after the first side is cut and use the same settings again, it all saves time, and they are so easy to make. I have even superglued a piece of metal to the inside of my vice jaws to act as a back stop when the diameter of my backstop rod was too large.
Pic 3 shows the first side machined, flip over and machine the other side, using the same setup.
Pic 4 is the finished job. Ten crankwebs machined in less than 30 mins.
Pic 5 uses the same setup for using a slitting saw to put the slot in, but two things here, after you have tightened up, remove the rods otherwise you end up with half round section, and don't try to do more than one at a time, it is by leaving the rods in for strength we can get away with it for milling the webs.
You don't have to use a slitting saw. a bandsaw or hacksaw will do the job, it isn't critical, but my way makes the bits look pretty.
Tomorrow we will get all the crankshaft completed and we will see if my calculations are right and the damned thing rotates.
John
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Hi All, back again. But not getting any feedback to see if anyone is still interested.
Who was the idiot who suggested building a composite crankshaft made up of thirteen separate parts (5 shafts, four webs and four cap screws).
Assembled it all, like trying to juggle with half a dozen kittens. Tightened it all up and the damned thing rotated perfectly, no fiddling, filing, nothing. So assembled the second one, exactly the same. So nothing else to do but carry on.
I knew something would go right eventually.
The sketch shows the different shafts required for the crankshaft, do not go over length on any of these, if anything slightly shorter (approx 0.1mm). It doesn't matter on the 60mm long one, this can be any length you like as it is the one that connects to your prop shaft.
When built there should be no shafting protruding anywhere into free space on the webs. The flats on the shafts are to allow grub screws to be fitted and the bruising to the shaft that they cause does not interfere with disassembly of the parts because the damage is on the flat rather than on the periphery of the shaft.
Photo 1 shows another way for machining the webs. I made a small shaft with about 5mm either end protruding out of the webs, these sticky out bits were turned down to 4mm (the same as the smaller shaft) and extended slightly inside the web. This method cannot be used where the shaft has to be removed for machining (cutting the slot) because the vice jaws prevent it from sliding out.
Second pic is showing all the bits for crankshaft assembly (my flats are not machined yet).
Pic 3 is the built up crankshafts, looking like they are ready for business.
My next job will be to make the bits to join the top and bottom together, namely the connecting rods, their screws and the support columns. Have got a bit of work to do on this yet as I need to keep the height to a minimum, so it will be conrods first then make columns to fit.
John
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Well I'm still following everything John. Not much to say as everything has been so well explained...
The assembled crank looks like a work of art - My hat is off to you sir!
The only thing that would concern me is assembling all those tiny bits with my size 19 hands! I wonder if I can talk my wife into getting interested in making steam engines, then I could get her to put all the fiddly stuff together! ;)
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OK, OK....I am bloody 22 thousand miles away....but yes... VERY interested John :bow
When I look at the electronic pages of steam engines by Daniel Bourard I see crank positioning referenced as degrees, minutes & seconds & naturally the same for the eccentrics [No I did not mean Sandy]
JMC [even after spending 610 EURO] will not release any working detail on this issue
So is this positioning a BLACK art or what & how do you achieve it ? :rant :beer
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Eddy,
Could you imagine trying to make a solid crankshaft. I can do it but I don't think the likes of beginners stand a chance, that is why I designed it this way, a few simple components making one complicated one.
I see you have fairly small hands then, mine drag along the floor they are that big.
Derek,
I think you are confusing your very well made and complicated slide valve engine with this simple piston valve design. The timing is almost exactly like an oscillator where each crank is at 90 deg apart (this gives it it's self starting properties), as for the port timing, Sandy explained this to me on a previous post about piston valve timing and basically the ports start to open 90 deg before the piston crank, at least I think that is what I mean. I wouldn't even know where to start on timing yours, maybe Sandy can help.
Did some prelim work this afternoon on the conrods, made a couple out of plasticard to get the right stroke so hopefully tomorrow top and bottom will be connected.
John
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I used to work for an angine reconditioning company John, and operated their offest throw crank grinder, so I can imagine some of the things involved with making a crank in one piece - I don't think we'll go down that road!!
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:D :D :bravo
Hi All,
Excellent job John.... I think you will end up with a great little engine.
This method of crankshaft construction is quite common on small model engines, Saito use a similar system, as do I on some of my engines.
It certainly is easier, cheaper and a lot quicker than turning the darn thing from a solid billit, however, it does have limitations.
The other point about this type of construction is the more simple method of making the crankshaft bearing blocks, which can, as yours are, be simple bored blocks. A fully turned crankshaft would need to be mounted in split bearing housings, possibly with split shell bearings as well, which are much more complicated to make and accuracy levels necessary are that much tighter.
With this method, it is also possible to use ball races on all bearings, which would not be possible with a solid turned shaft, at least not for the centre bearing/s.
On larger engines it would be possible to use split roller bearings on the inner journals, however, for these small engines such items are not readily available. (at least not at a practical cost)
Valve timing..... The inlet port should begin to open when the piston is at top dead centre, or just leaving it.... with a simple piston valve, as John is using, this means that the crown (high point) of the eccentric must be ahead of (lead) it's associated crank pin by 90 degrees. This angle is quite critical and therefore must be accurately set.
The crank timing of 90 degrees between cylinders, which is not overly critical, +/- a couple of degrees would not cause any real problems, has nothing to do with the valve timing, this is, as you say, to enable the engine to be self starting.... however, this is only true when using double acting cylinders. (You would need 4 single acting cylinders, each set at 90 derees to each other, to achieve the same effect)
Derek..... your JMC also has 90 degree crank spacing, however, since it also uses Stephenson link valve gear with 2 eccentrics per cylinder and probably also employs some valve lap and/or lead, then the eccentric angles will not be at 90 degrees, but would be set at some angle as dictated by the valve gear type and the lap/lead requirements.
The next instalment of Steam and Steam engines will be dealing with just this subject, so hang on just a bit longer and you will be able to read all about it.
Ok, that is my two pence worth.
Keep up the good work John.
Best Regards.
Sandy. :vacat :computer :beer
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Sandy,
Many thanks for your words of wisdom, you can explain these technical bits a lot better than myself.
As I said at the beginning of this article, everything on here should be able to be made by a beginner so there would be no complicated bits to make, just be fairly accurate.
I am on a learning curve on this one, never having built a piston valve one before, I don't have access to any examples of what other people have designed and made, I just look at a problem, see what may work and make it, luckily up to now everything has worked out 100%, just by using good engineering practices. I have yet to fall on my a**e, but one day it will come, so I will take one step back, one step sideways and carry on. There are usually a lot more ways to solve a problem.
So in maybe a weeks time I will be trying to set the steam ports to the correct timing, its easy making the bits, it is getting them to work in unison is the problem., so your comments might be called upon again.
Thanks again
John
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Didn't get as far as I wanted today, the great one got me scrubbed up with a hose and broom and I had to go, dare I mention it, SHOPPING. Aren't supermarkets wonderful, I always wondered where all our food came from.
Anyway, managed to get top and bottom joined together, so I took a couple of pics to show the development. The conrods are still not finished, the front one is what I expect it will look like, the rear is just the basic building block. And the thing still turns over, a bit tight, but that is easily remedied with a file and a hammer plus a bit of oil. I rushed these conrods so I think one of the holes isn't quite parallel, but as these are tryouts I am not worried.
You will notice a couple of raindrops in the background, twenty seconds later we were into a full thunderstorm. The dog can go for a walk by itself tonight.
Clean John
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Hi All
Got the top and bottom joined with the right bits now.
First the sketch. This shows the dimension for the column length. As stated in a previous post about the thickness of plate used for the block support plate. This dimension is for a plate with a thickness of 2mm, if the plate you use is thicker then subtract the difference from this length, if it is thinner then add the difference to the length. If you don't do this you will end up with a mechanical lock on the engine. The columns can be any diameter from 6mm to 10mm, it doesn't matter, but if you use aluminium for the columns I would go for 8mm and above.
Also shown are the dimensions of the little end pins.
The conrods are shown as a raw shape, the engine will run with them like this, but you can hack to your hearts content as long as you don't get too close to the bearing holes and don't reduce the diameter to less than 4.5mm, you can have it square or round, maybe profile it like a car conrod, drill holes thru them, it doesn't matter, let your imagination run wild.
The first picture shows how I developed the conrods, starting left to right, a bit of plasticard, just to see if I was in the ballpark, then a couple of rough, and I mean rough made to check for correct length and dimensions. The next pair are the same except one was profiled to see what it would look like, these were correct dimensionally. The last are the finished rods and pins.
The second pic shows the engine with the new rods, I think it makes it look very beefy and powerful, what do you think? Also shown is a ruler against the engine, from the wrong angle, but it shows that the engine is about 4.5" high and it is the same length and 2"wide, not minute by any means but it should shove a boat of 4ft or over along quite easily. Sorry about that I have just reverted back to imperial, damn this government.
Now a question from me. Is anyone building this engine as I go along? Or as I suspect are you hanging round like vultures to see if I snuff it before I finish, or make one holy cock up of the whole thing so we end up with an engine that won't run.
Oh! ye of little faith, this engine will be finished, even if the dog has to do it, and if it won't run I can always put an electric motor on it (hidden in a box behind the engine), so it looks like it runs.
Anyway, joking aside, I have a question to ask as to what type of speed control and reverse you want on this engine. Basically there are two that I will consider, the first is the usual type that is a rotating disc. These are easy to make except for the disc itself, they have to have fairly accurate transfer grooves machined on them and do require a rotary table, I know you can use straight transfer grooves, but I have never really found them satisfactory, also these controls tend to leak steam even though they are finely bedded in.
The second is a control block where everything is sealed inside and doesn't leak, but it does require the use of a small o-ring to seal the output shaft (I would consider supplying the o-ring if you sent an SAE. UK only), and the machining has to be fairly precise, but if you have got this far in the build you shouldn't have any trouble making it with the experience you have gained already.
The reason I have to ask is that I will be designing the piston valve area this next week and it all depends on which one is required determines where I should put the inlet/outlet flanges on the blocks.
If you don't give feedback I will be going with the second option.
I won't be posting for about a week while I design the blocks and iron out any problems, but I will keep checking the site to see if there is any feedback. Last chance to vote is wednesday evening.
John
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***************MODIFICATION***************
I was doing a bit of design work tonight on the piston valve control block, and have decided to change the internal port sizes to allow for easier setting up. This means that the eccentrics will now have a different throw.
So the text for the post concerning the eccentrics has been changed and a modified sketch has been uploaded.
If you have already made them as I have, at least you now know how easy it was, and they get easier the second time around.
John
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John, is there a reason for the fourth main bearing after the flywheel?
I think the engine would look a lot nicer without that bearing (personal preference), so I'm wondering if it's needed, or if it's just the way you do things?
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Hi PD's..... just a few observations from Johns postings...
1) from Sunday @ 5.35 to Sunday @ 7.51 is not a lot of time to shop for Vegemite, Garlic & a few packets of fags & :coffee & some dog & cat food.... let alone more machining :crash & complete more of the engine assembly
2) I certainly have been watching each day in awe John :post & :kewl
3) Eddy... I acknowledge other engine manufacturers of similar style engines may not have a bearing journal outboard of the fly wheel, however consider the advantages
a) the additional bearing is machined & lapped on true axis with the other engine bearing journals
b) the inclusion was of little time or effort [just one more identical block, a few socket head cap screws & an extra pin]
c) the engine starts out converting up & down motion, then to rotational movement @ the flywheel,.... outboard of the flywheel the physics of nature want to revert the [resultant] loading back to push pull [in both longitudinal & diametrical axis]
d) this additional outboard engine bearing minimises the requirement in the next line of diametrical power transmission [bearing] support
So 10/10 John for bogstandard robust design :trophy..........
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Hi Eddy,
The reason as Derek kindly pointed out is an engineering issue.
If the bearing between the crank and the eccentric on the flywheel end had been a lot longer and had a substantial support bearing in there then the fourth bearing could be omitted.
As it stands, the weight of the flywheel is trying to go downwards at an angle and will put a lot of wearing forces onto the bearing, so the fourth bearing ensures the downward moment of the flywheel is reduced, thus causing less wear.
I told you that this engine will be functional rather than pretty, but it will look a lot better when the steam chests go on.
John
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Hi all,
Got on well today, have got basic plans for steam chests and piston valve. a bit complicated because the block is so narrow, I couldn't use any internal porting, plus I needed to bolt the thing to the block so it took a fair time to get all the holes missing each other. I will knock up a couple of blocks tomorrow and see how it all fairs. In hindsight I would have made the blocks 10mm wider and gone for a 15mm bore, but one of the criteria was that I used as much material from the scrapyard as possible, and this was the largest block I could get out of the sash weights.
Have come across a major problem, as you know I was trying to keep this engine totally metric, but unfortunately my supplier doesn't stock 3mm copper tubing, so we will be using 1/8" instead. When I eventually put up the drawings, if you see any pipework or steam fittings mentioned on there, the relative holes will be marked in imperial with all other measurements in metric. If you only work in metric, 1/8" is equal to 3.2mm tight fit, or 3.3mm sloppy fit, so it would pay to invest in a 1/8" drill.
I have got to get on with this at the moment, so I am designing around a sealed control valve, I have another commission this weekend so I want to get as much of this done as I can, so expect the next instalments sooner than I said.
John
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Back again,
It's been a bit of a long haul this week, family commitments and all that other unnecessary rubbish like 'can you go and pick the grandson up from school', its only 3 miles, are they incapable of walking any more.
Anyway, managed to get it all designed, but all machining hasn't been done yet. The making of the piston valve control block will be done in two parts, the one here now gets all the holes in the right places, the next post will show what milling has to be done as the sketch would get very complicated if both were put onto the same one.
The sketch shows all hole positions but they are drilled in a sequence to prevent burrs destroying the smooth cylinder walls.
Here goes.
Pic 1 shows the correct size for blocks. Mark one small end and this will be your datum face.
The first op is to drill the 5.5mm hole as shown on the sketch small end, drill 36mm deep (including pointed drill end).
Second op, on the 16mm side you will see two 3mm holes and four tapped 2mm holes. These are all drilled thru to meet the 5.5mm centre hole all except the top one which is drilled 8mm deep. Tap the 2mm holes.
Third op, all the holes on the 18mm side are drilled all the way thru the block. The 3mm holes are the steam control holes and the centres between them need to be exact, so rather than marking out and drilling, use the machine feeds to get this spacing.
The four 2.5mm holes are for mounting the control valve to the main block (how this is mounted will be explained later).
All holes should be deburred but the four ends of the steam control holes should only be deburred very lightly.
The final op is to run a 6mm reamer down the main central hole, this will clean off all the burrs thrown up on the inside and leave a nice clean hole for the piston rod to run in.
Don't worry about the 2mm tapped holes going into the bore, these will be sealed with a screw when the flanges are bolted on and the bit of tapped hole left on the inside should act like a reservoir to hold a bit of oil, and it makes them a lot easier to tap.
Pic 2 shows all the holes required on the block.
Remember a couple of posts back where we made the conrods and I said to use your imagination, well pic 3 shows the rods I have made for my second engine which is going to have a makeover as it is being built to try to spice up this utilitarian design. You will notice that they are a different colour, they are made from aluminium bronze, a lot lighter and stronger than brass (another choice product from the scrapyard, recognizing what it is while rummaging is the problem).
John
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Now for the second part of machining the piston blocks.
Just a word of warning, you have to make an opposing pair, so mark everything up so you don't ruin your day.
The first part of the sketch shows you the position of two slots you are going to mill out, they are to join the main piston valve ports to the ports on the main block that go to the top and bottom of the pistons.
I would suggest you bury the cat, superglue the dog in its basket, give the kids some money to go out and treat the wife to a girlie dvd, you do not want to be disturbed while machining these slots, go past the line and you are having a bad day, unless you are good at rebuilding with silver solder.
They should be 2mm deep and up to 3mm wide, I have made mine 2mm wide. if you look at pic 1 it shows how I marked them up.
The lines are marked from the same datum as we used to drill all the holes in the previous post. The top and bottom marked lines are absolute limits, do not go beyond them, I would stop about 0.2mm from the line.
Once you have done one, mark up the second to give you an opposing pair and machine to the same criteria as the first. They should look like the ones in pic 2.
Once you have your pair, now for a bit of cosmetic machining to make it look a lot better.
The second part of the sketch shows what is to be hacked away.
In pic 3 it shows the hatched areas to be cut away, nothing too critical but try to make the height the same as the main block just to keep it looking neat.
Pic 4 shows what you should end up with.
There is a bit more to do on this block but it is to do with a gland seal like we have on the main piston rods, but that can wait until later. I have to finish the posts now until sometime next week as I have a couple of commissions to prepare for delivery.
On the next one we should be able to get the block joined to the engine and make all the bits to connect to the eccentric. Once this is done we can get some air to it and time the lot in. After that it is just a matter of getting the pipework and control valve done, so we are fairly close now.
May the force be with you.
John
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Hullo PD's .....well.... we can see John is progressing at a great rate of KNOTS :clap, but how optical illusions still occur via computers
In '3 Custom Rods .JPG'.....we see the three lightening holes in the cranks for engine 2
In '1 Blocks marked for the maxcut.JPG'.....I thought I noticed the alternate set of cranks for engine 1, however which had been :hammer milled for the length of the throw to create an inboard sculptured appearance.... so talking with :gather a few OZ colleagues & a :beer we all agreed they appeared a very attractive rendition over the lightening holes
Then one smart ar..e [who is really only a 1/2 baked KIWI] said :nono ...it is only an illusion... look at the transition toward the big-end...... :rant & :sorry ....but it still looks good [neo-classical] :?:
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Hi Derek,
I think I have the gist of what you are talking about, the rods on engine 1 are in fact just turned parallel, and what is seen is in fact an optical illusion, most probably caused by the angle the photo was taken from (I think it is called parallax error).
The custom rods again are turned parallel but the three equi distance holes are of different sizes, namely 3.5, 3 and 2.5, to give the illusion, from a distance, of a tapered conrod.
On engine 2 I will be doing some taper turning on the columns, but I didn't want to complicate things for this basic engine.
John
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OK PD's...... when John mentions - "I will be doing some taper turning on the columns"... reminds me of Tubal Cain early steam component construction......beautiful :bow neo classical [non necessarily functional :nah ] but still :no1
Eighteen months ago I incorportated a basic element of this style of :hammer construction in the arched support for my JMC3H engine...... as per earlier postings
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Just for Derek
Here is a little poser for you and your mates in Oz. seeing you spend more time looking into the background rather than at the piccies themselves.
You must have seen this little item in the background of some of my pics.
I designed this myself and it saves me hours of grief and stops those bad day blues.
It isn't going off topic because I use it all the time in making these engines. Usually a few times a day.
The four rods are a specific height from the base, and are sized 3,4,5 & 6mm.
It is used in conjunction with other pieces of equipment (I've most probably given the game away now).
I hope this will keep you occupied until I post again.
And it isn't a mini capstan for people with different sized hands.
John
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Well you've got me baffled John, but it doesn't take a lot to do that!
My vote goes for a 1:24 scale capstan for crew members with different sized hands ;)
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Hi Eddy,
You said exactly what I thought they would say, you must have posted at the same time I was editing my post to tell you it wasn't a capstan.
John
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Hi PD's............... & yes John ... it was a very :thinking my :angel grandfather who suggested that I must look VERY deeply into the background prior to making comment re the current..........
With respect to your "four column height/length gauge" .... we convicts used these as toys on the voyage :vacat to OZ for over sized or undersized marbles [when the deck was steady] :hehe
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Way off
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OK PD's :rant :nose ... lets play John's guessing game :hmph :music
1] the column has four sides - each face does not exhibit pressure marking as being held in a vice or four jaw chuck - similarly the top face is not centered so would also suggest as not held between centers
2] each face has a different diameter shaft on what appears to be = height axis on center from the base
3] the lengths of the four respective shafts to the block faces also appears to be equal {however this is a RED herring..I think}
4] the ends of the respective four shafts are flat so are not used as a scribing reference
I previously :shoot blundered as a 'four height/length' column... however this was adjudicated as incorrect
Is it a jig for holding components which have holes of 3,4,5 & 6mm diameter pre drilled? whilst completing further machining processes?
People from OZ are tough :yeah .. we never give up.. time to help cook the Sunday roast & have a :beer + :thinking more :rant
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:nah ... Oh PD's ... as resourceful as we are... try & search for the "metal to size and marked up.JPG" dated sometime in this year of our Lord............ :nono but I won't tell :hehe :music :luck
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Nearly there, wrong on the machining. Another process follows.
The picture you found tells it and shows it all, except for one vital piece.
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OK John :nah .... see how you like the return quiz but :shhh .....[I booked a community call to Sandy & Walter & TBJ... as these members [as I] had professional :nose training in t**ing in music all those years ago
So my final answer is "t**e, "t**e, "t**e is on my side":......by Jagger & Richards........ :music :music :music.........
If I am again incorrect PD's .... I promise no more :hmmm :shoot guesssssssssssssses :sorry :hehe :hehe :hehe
PS..... Kate won't let Sandy respond on the PC :nono as he hasn't finished the new kitchen :crash :hammer renovations
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T**E has definitely run out for you my man.
I thought you would get it straight away when you found the other picture with a square right next to it.
The solution is shown on the piccy.
It is used to set up anything with a standard size hole (and even non standard sometimes) into my toolmakers vice so that I can tap the hole using my vertical tapping stand perfectly square to the bore. It only takes seconds to do, and by the way the jig is removed from the bore before tapping.
I have finished my commission jobs so I will be posting very soon.
John
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Well PD's,,,,,,, we know John is a self admitted no nonsence :nono task master.....but how do I explain my $500.00 AUD [to Karina] telephone bill to Mick & Keith when TIMING was not the answer
But remember ....we people from OZ are tough :weight .. others eat MARS Bars......we eat IRON ORE crumblings on our weet BIX :great ....we never give up :towel
Edited------ yes ....I can see the jig-function in easy setup John......etc
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:D :D
Hi PD's,
I tried to post this last night, however, I was having problems with the PD's server, which would not connect...... maybe Eddy was uploading to many video's or some such..... :hehe :hehe :music
Anyway, why is it when you start a job, something always happens to make it a much bigger job?
As some of you know, I am in the process of upgrading the domestic galley area..... took the old wall units down earlier in the week.... you geussed it...half the B****y ceiling and a good chunk of wall plastering came away with them....... result... a further weeks work to get back to where I started...... :( :( :( :evil: :twisted: :rant
Looks like ACS are going to be down for a while longer than anticipated...... such is life.
Kate is not very happy either.... no sense of humour some people.... :oops :sorry
John..... good to see you are progressing well with the engine design, I particularly like the way you have achieved the steam transfer passages.... certainly saves a lot of deep drilling and plugging of holes afterwards.
On the subject of deep holes.... I attach some notes which may help any of you who may be following John's build, especially those who may be first time builders.
In no way should they be considered as any form of criticism of John's most excellent article, but merely as helpfull tips towards getting the job done successfully, and with as few tears as possible.
As John has already stated, the purpose of his postings was to pass on the design as a whole, along with general processing methods, rather than a blow for blow acount of how each piece was/should be made.
Having already mentioning the deep drilling issue in an earlier installment, I felt it would be helpfull/usefull in this instance to enlarge a little upon the subject at this point.
There are, of course, many ways of achieving the deep hole required, these notes are just one possible method, and one which should be achievable by most of you.
I am eagerly awaiting John's methods on the manufacture of the piston valve bobbins, and his method of timing the valve gear. :respect :respect2
OK BACK to the KITCHEN..... I know my place.... :twisted: :evil: :( :(
Best Regards.
Sandy. :coffee :beer :beer
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I would like to thank Sandy for the post on deep hole drilling, very informative for everyone. My problem is that I have all the correct tooling and machines to carry out all the machining with ease and I keep forgetting that novices will not have access to the type of equipment that I posess, like most of my drills are precision four facet ground, plus I also have a set of metric drills specifically for drilling brass where the front face has been ground vertical to give a zero rake. To buy all these items at the beginning would cost a fortune, so purchase the best you can afford, you will find they will last a lifetime if correctly looked after. Most of my machine reamers came from the scrap man, who also clears out industrial workshops, and bought by the kilo. the last lot I bought were all brand new small metric (smaller than 10mm), solid carbide. I paid £20 and got about 25 reamers. The cost for one would be at least double this from a tool specialist. So if you really want to it can be done on a tight budget, you have just got to search about a bit.
Many thanks again Sandy for your input.
John
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Now we are cooking on gas, starting to get it looking like a finished engine.
There is no need for a sketch for this post as it is done with piccies and superglue.
Pic 1 shows the size of the blanking plate for the end of the piston valve block, mine are made from the same material I used for the block support plate, 2mm thick brass, but I suppose they can be made of steel or ali, just don't go too thin as they are blanking plates for the steam control ports. I stuck mine together with double sided tape to allow me to machine all of them in one hit. You will only require two if you are making one engine but twelve if you make six (confusing isn't it).
Once you have the plates made, carefully superglue them to one side of the piston valve block and spot thru the block mounting holes with a 2.5 drill, this will give you the marks to drill all the way through the plates, you should end up with plates as in pic 2.
This time stick the blocks to the main piston block (the big shiny one), (too many pistons in this game, I'm going home) and carry out the same manouver by spotting thru with a 2.5mm drill. This again will give you your drill marks. Drill these holes with a 2mm drill 7mm deep and tap to 2.5mm.
By the way, the reason I always drill and tap so deep is that I am lazy. By drilling so deep it allows me to use a taper tap and get about 4mm depth of good thread, rather than drilling 4mm deep and having to use both taper and plug tap. At my age time is precious.
********** WARNING *********
Look at picture 3 and you will see the lower holes marked as a danger area. The reason for this is that when you drill these four holes they will penetrate the remnants of the holes that were drilled for the plate mounting screws, so unless you want to keep the DIY stores in business by selling you 2mm drills, take it VERY slowly and steady after you have penetrated about 2mm.
I will post a sketch tomorrow for all the hole locations if you do not want to spot thru. The reason for this is a fellow member of P.D.'s has kindly offered to draw up the plans for this engine, and this sketch will be needed. So hopefully after the end I should be able to upload a good version rather than all my grotty sketches.
Back to the build. Now you should have two plates drilled and deburred, and one main block with four holes extra in each end, that is eight all together, any less and you need to check again, any more and you are in trouble.
We now need to join all the bits together, so I thought I would give you a choice, one is rather expensive, the other is dirt cheap if you know any stainless steel welders. The first option is to buy some long 2.5mm bolts (I bought mine on a visit to Germany many years ago) and use those.
The second option is to use 2.5mm studding. I made these yesterday (Sunday), and I thought to myself 'Where can I get 2.5mm stainless studding on a Sunday', in fact where can I get it period. Then it occurred to me that a friend had given me some stainless welding rod a while back, I measured it up and it came out to 2.37mm or near enough for what we want. I needed about 350mm of the stuff, so lathe into very slow back gear, out with the die stock and die, and having about 75mm sticking out of the chuck at a time with plenty of cutting compound, within 10 minutes had what was needed (miles quicker than making individual studs with a thread at each end). See pic 4.
I cut these into 26mm lengths and joined all the bits together, see pics 5 & 6. I am lucky, because I am building two engines I can have both, but I suppose you could mix and match if you were that desperate.
Next time the engine will be built up again and I will be making the eccentric straps and the piston valve control rods (a bit of high precision turning), but by now these will be a piece of cake with all the experience you have had so far.
These might take a couple of days for me to make and draw up so don't hold your breath.
John
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:D :D
Hi all,
No problem John, I had a feeling you would see where I was coming from.
Like yourself, I am surrounded by similar large equipment and have many options/methods available to me in achieving a particular end.
I also tend to sometimes forget that others are not necessarily so well equipped and might find a particular process, second nature to us, quite daunting, especially when the main machines available may be a small lathe and a small bench drill. It was for such people that the added notes were intended.
On the subject of tapping holes, I use a slightly different approach, but for much the same reasons, I am also lazy, getting old and time is precious, so, like you, changing from taper tap to plug tap is not on.... I use spiral fluted taps, which are magic for blind holes and only one type is needed, namely the plug equivalent, which will tap a full thread right to the hole bottom.
The other advantage of these is that they throw the swarf out of the hole as it tends to climb up the spiral flute rather than falling to the bottom of the hole.
A small point on the availability, or not, of 2.5mm bolts, especially in the UK..... substitute with 7BA (use a 2.05mm tapping drill followed by a 7BA tap) which are readily available in hex headed form, even in stainless steel, from many of the model engineering suppliers.
Ok thats my lot.
Best regards to all.
Sandy. :D :D :vacat :computer
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Hi Sandy,
Little would you believe it I have loads of the spiral flute taps, exactly as you said. But my problem in the frantic rush at the scrapmans emporium when a new load of tooling came in and I saw all the small metric sizes I snatched his hand off fairly quickly. Anyway a couple of weeks later I came to use one of the taps and just looked to see what size it was and noticed the word HELICOIL on the side. Never used them yet, but did manage to get a load of inserts just in case.
By the way, the design I will be using for the 'bobbin' valve (I would in fact call it a spool valve, from my days in pneumatics) is the one you told me about, being drilled from one end with an outlet hole just below the lower spool. I have the machining sequence already tried out and seems to work ok, can be tackled easily by anyone and should produce a good valve. Thanks for the design idea, it has saved me hours working out porting to get from top to bottom.
Sorry if this post has baffled anyone, just a quick explanation on the word helicoil. Helicoils are usually a steel thread insert put in to either repair or make more hard wearing a tapped hole. The taps are marked up as say 3mm, but in fact they cut a lot larger to allow the insert to be fitted to bring the hole back to 3mm size. So the ones I bought were no use for tapping standard size holes - DOH!!
Now you see the reason for my signature.
John
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Goodness PD's.... the sight of grown men :mrgreen: rushing down stairs @ 6.00 AM to the :computer to catch the latest renditions from John & Sandy........:clap :post ......thank goodness the :coffee is on
With all this talk of :hammer tapping things.... you may wish to confirm to PD's on the current best practice fluids for this tapping process.... as my references are from the First Fleet only [1878] & I am sure there must be some advancement since then :darn
For aluminium a small drip of kerosene only, for aluminium bronze we couldn't afford anything, for red brass...one little drop of RocoiYel, for steel....one little dollop of that green slime TREiFolEX
Don't you just love our inherited language.......like what is the difference between a small drip .....a little drop and .....one little dollop :?: :idea: :hehe :music
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Hi All,
I will just answer Dereks question first. When tapping I tend to use Rocol cutting compound for almost anything except for cast iron which I always cut with no lubricant at all. Machining metal is a totally different process, and as you said, paraffin for ally, standard water soluble cutting oil for almost everything else. BTW for cutting copper (one of the worst materials to try to machine, it is like trying to machine evostik glue) try cows milk as a lubricant (if you can get the cow past the wife without her noticing), I suppose Derek could use his famous Ozzie goatsmilk, but I think the smell would be a bit offputting.
BTW I see you rise late in Oz. By 6am I have done the 3 Sh's, walked the dog about a mile and sat down to weetabix, coffee and a fag, in that order. Then its usually time to read the new posts.
That brings me onto this post. Only one pic tonight (the drawing mentioned last time will come later), the engine built up as far as I have reached with a pile of raw material to carry out the next task. That is to make the spool valves, and the eccentric straps.
The crankshaft is already timed for running, with pistons and eccentrics in the right positions (or so close it will not matter). If you remember when I showed how to make the eccentrics and I scribed a line on the back when I drilled the thru hole, well the trick worked a treat, you can align everything very accurately by eye rather than having to use a DTI to find max lift. So if you can, put that line on, if you need to know how, just ask.
Now the bad news. For the next week or so I am going to be very busy outside of the workshop and won't have time to prepare the posts. So what I intend doing is to get in the shop as much as I can and get the engine to a running state (no control valve, just fill it full of air). Once that is proven I will catch up with posts and pics. This part of the engine build is the most critical bit and hopefully should go fairly smoothly as I have already planned most of the machining stages, making the bits is easy, it is the fine tuning to get them to all run in unison that takes the time.
I will still be reading the posts and can answer any questions you may have.
John
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I have to admit that I initially thought the engine looked a bit ugly - Sorry, but thats the honest truth.... I realise a lot of the engine is designed to make it a relatively easy project for a newcomer, and we were looking at bits and pieces rather than a finished product.
However, now that it's coming together I'm starting to like the look of it more and more.
So you must be doing something right John! ;)
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Hi Eddy,
I love it when people give their truthful thoughts about something, there is absolutely nothing wrong with that.
If you remember at the beginning I said this engine would be functional and totally ugly. I think I have achieved that with gusto, but I must admit it does grow on you when you see it every day in the workshop, screaming to come to life, I can't wait to give it a few more bits, and it should look even better (but still ugly).
John
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Thanks for being so understanding John - My comments certainly weren't meant to be offensive, just an honest opinion....
However, as I said, the engine is definately growing on me as it progresses - Though as Walter Snowdon and Bob Golder (two fellow clubmates) would probably tell you, I do tend to like slightly quirky and unusual models, so it's perhaps not surprising that your engine is having more and more appeal as a potential first project! :)
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Hi PD's...glad for the clarification on the new renamed ROCOL product John - it appears that TREFELOX is actually scrunched up OZ green locusts... hence the :offtopic smell oh well..
You had previously noted that a kind PD had offered to commit all of your all of your sketches to Drawings....would this be in an electronic format :?:
Talking with a few colleagues :gather & one suggested... if yes in electronic format, would be simple to redesign
1) the base plate to place the crank to piston axis on a 30 degree diagonal to the horizontal
2) the cylinder mounting block as above
3) the bigend bearing blocks similarily modified [so the oil didn't fall out] both North or South of the Equator
& hey presto a :no1 paddle engine
The same bright spark also suggested he had a source of 4 & 5 mm diameter Torrington needle bearing needles
Anyway contrary to comment we people in OZ think the engine looks tough enough :yeah for our harsh OZ conditions & the manufacturing text is :news for anyone considering a build
But :thinking , your engine MUST have a name & here is my entry
"The J*** No1 V S******D"....what do you think PD's :?: :hehe :music
Edited to add a V for......the opposite to H = horizontal or......different from D = diagonal
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Hi Derek,
I thought you lot ate all these creepy crawly things, not mashed them up to make lubricant. otherwise the Bushtucker man is telling us porkies.
It is still in the early stages yet but I think he is doing it in CAD, so supposedly it will have the facility to be modified. The problem is that he cannot visualize some of my sketches so I will have to redraw them.
I definitely considered turning this engine into a horizontal, but the sheer width of it has put me off the idea. It would be better, if you can imagine it, cut the main cylinder block in two, and rather than having two steam control blocks just have one between the now sawn in two cylinder block, with a dual eccentric in the middle of the crankshaft. Doing it this way a saving on width of at least a third could be achieved. But there would have to be a redesign on the crankshaft to get it into a narrower package and I think this would be, for the moment, beyond the skill of the people this article is aimed at. But if they manage to complete one of these with such bad sketches, I'm sure that with a little bit more encouragement they could trespass into the realms of one piece cranks (not from a single billet, but built up as these are and silver soldered together).
Lets get this one finished first.
John
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Hi PD's & a few points of clarification John...Q=question, C=comment, A= answer, R=response
Q) thought you lot ate all these creepy crawly things, not mashed them up to make lubricant. otherwise the Bushtucker man is telling us porkers
A1) what.. do you think we are all silly :nose :!: .....we wouldn't eat that crap
A2) we don't have a "bushtucker" person in OZ - rumor is that your version is a Scot via a non deplume :music
C) It is still in the early stages yet but I think he is doing it in CAD
R) well thats good
C) the problem is that he cannot visualize some of my sketches so I will have to redraw them.
R) if he cannot decipher your scrawl from the first sketch who will provide the second sketch :?: ...the Dog :?:
C) I definitely considered turning this engine into a horizontal, but the sheer width of it has put me off the idea... lets get this one finished first
R) acknowledged & :bravo :news....you have just got-a-laugh :hehe
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Hi Derek,
I admit defeat on all your answers except one, why drag my gifted friend the dog into the argument, I told you before, he's the maths expert, the cat is the artist!!
But you must admit since I robbed my grandsons ruler and pencil (I must stop all this contact with convicts, I'm turning out just like them), the sketches have got slightly more decipherable, in fact the dog has no trouble reading them at all, once he puts his contacts in :shock: .
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Hi All,
Ever since Sandy did his post on here about deep hole drilling it has been gnawing on what little mind I have left about the difference between hand and machine reamers, and I should have mentioned it without someone else having to remind me.
So I have decided the easiest way is to show you where you can get machine reamers at a very reasonable cost.
It is here - http://www.tracytools.com/reamersassorted.htm
The pic I have posted shows my imperial set that I obtained from them, 1/8" to 1/2" in 1/32" increments for about £70. They aren't all the same design but they all are good quality and function well. I think they do metric machine sets as well. The best way to order is to give them a call and tell them what you need, as the website is a bit confusing at times.
Another thing to note when you are just starting out is that the machine costs are negligible compared to the tooling costs. Only buy what tooling you require to do the job and over the years you will eventually end up with everything you require to complete most jobs. Car boots and private ads are a good way to buy tooling. A chap on a boot sale was selling brand new metric milling cutters (I didn't ask where they came from), various sizes for £1 each, I offered him £30 for the box and ended up with over 100 cutters. Went to a model boat show and a chap was selling what he thought were 2mm resharpened solid carbide drills for £1 for a pack of 10, they were in fact HSS 2mm slot drills, I bought the three packs he had left (some of his previous customers were in for a shock when they tried to use them for drilling). So keep your eyes open all the time and your machining can get a lot cheaper.
By the way, the engine is getting very close to running, will post a vid as soon as.
John
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Hi PD's ... & as John says....ever stop to think, and forget to start again? :nono that's not correct yer fool Derek :sorry
Have placed a few OFF line calls to John....turns out he has been VERY busy... the DOG is about to sit for university entrance tests & needed a BRUSH up on his maths........, the CAT sat in the paint pot & needed lots of brushing too...& to top this.....the grandson has taken back the pencil & ruler............. :ohno...its OK PD's..... I have posted another REAM of A4 paper & a few OZ pencils to John :hehe :music
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Hi all,
Back again at last. Many thanks to Derek for waking me up. Haven't got the paper or pencils yet so I have got a piccy to show you.
It shows the engine prepared for its first main run, you can tell the size of this monster by comparing it to my gorilla sized hand.
It has been assembled just from the made components with no rings, gland packing or sealant, also the timing has only been quickly done (near enough). So really this engine is leaking air from most of the joints and so is most probably only running at about 50% of its capabilities.
I will be posting soon all the components that have been made over the last week or so. Some like the spool valves I will dedicate a complete post to, like I did about the eccentrics, they are really easy to do once you get the correct machining sequence.
Anyway, have a look at the pic then go here for a quicky vid to show you that it does work.
John
http://www.youtube.com/watch?v=QwOhxvGc5VY
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VERY impressive John!
Will you be taking us through the complexities of making a steam regulator/throttle for the engine once you've caught up with all the other bits you've made over the last week?
How big is the video? It would be nice to have it stored on Paddleducks so it's always available here - I never trust third party sites as you have no control over them and things can go missing. Maybe you could send it to me via email and I can put it online for you? admin@paddleducks.co.uk has a 20Mb inbox.
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Hi Eddy,
Glad you like it.
The video is in fact nearly 53mb, but I suppose I can get a program to reduce the size below 20mb, but you will lose quality, as it has already done so on utube.
Yes, I have got the design of the speed control valve in my head, its just a matter of getting it made and working, it isn't my design but a modified one to make it easier to produce.
It will take me about a week to catch up, but I am feeling a lot more confident now that the design has been proved.
I would like to take this opportunity to thank Sandy of ACS for the help he gave me in explaining the operation of the valve gear, which enabled me to get it all to work in unison.
John
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Very nice what boiler does it use ?
Regards Woody
From: "bogstandard" <livesteam@paddleducks.co.uk>
Reply-To: livesteam@paddleducks.co.uk
To: livesteam@paddleducks.co.uk
Subject: Re: Making a piston valve engine from mainly junk materials
Date: Tue, 03 Jul 2007 19:54:42 +0100
Hi all,
Back again at last. Many thanks to Derek for waking me up. Haven't got the
paper or pencils yet so I have got a piccy to show you.
It shows the engine prepared for its first main run, you can tell the size
of this monster by comparing it to my gorilla sized hand.
It has been assembled just from the made components with no rings, gland
packing or sealant, also the timing has only been quickly done (near
enough). So really this engine is leaking air from most of the joints and
so is most probably only running at about 50% of its capabilities.
I will be posting soon all the components that have been made over the last
week or so. Some like the spool valves I will dedicate a complete post to,
like I did about the eccentrics, they are really easy to do once you get
the correct machining sequence.
Anyway, have a look at the pic then go here for a quicky vid to show you
that it does work.
John
http://www.youtube.com/watch?v=QwOhxvGc5VY
------------------------
Ever stop to think, and forget to start again?
Attachments:
http://www.paddleducks.co.uk/forum/files/ready_to_have_first_run_519.jpg
Post generated using Mail2Forum
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you can tell the size of this monster by comparing it to my gorilla sized hand.
Notice the knarled fingertips - Definately the hand of a borne engineer! ;)
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Hi Woody,
No thoughts on making a boiler, but a commercial 3.5" one should power it ok. I said in an earlier post that if I was designing this without the limitations on material sizes I would most probably make it with a larger bore. The physical size of the engine is rather large compared to my twin cylinder oscillators which use the same bore and stroke.
Eddy,
I wouldn't call them gnarled, just well used. Thats what hands were made for, its just that people use them in different ways :nose
Tried to send a resized vid to you last night, and it was returned because it said your box was full. I have resent this morning, see if that fairs better.
I will be drawing up some bits today so will most probably post tonight about the spool valves.
John
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OK PD's.......it is easy for me being 20,000 km away & :post ... the machined & assemblied engine is :no1 & :kewl .... however don't give up the day job John... as your 1/8" copper temporary pressure inlet source looks :hammer :oops in need of a STRAIGHT/STRAT/STRAIT piece of tubing....you know what I mean :hmph
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What do you mean Derek, 1/8" copper temporary. This is finished product, all my pipework looks like this, gives it a 'used' look.
And now, the 'easy way' to make your spool valves. This is a rather lengthy post but it goes thru step by step how to get useable spool valves.
The first thing to do before anything else is to look at pic 1. Put two pieces of close fitting rod thru the two steam port holes. Now measure close to the block, to the outside of both rods on each side and take a mean measurement, that is if one side measures 18.96 and the other 18.98 the mean is half way between the two 18.97mm.
I decided from my four readings to go for 19mm, on no account go for anything shorter than the largest of your mean reading. This is going to be the distance between the ends of your spool valve.
There is no picture of the next step. Cut a length of bar to 46mm and just face both ends. While the bar is still unmachined and rigid drill the two end holes one 24mm deep by 3mm diameter and the other 10mm deep by 2mm diameter, and tap the 10mm end out to 2.5mm.
Put the untapped end into the chuck (I would recommend making a split brass collet to protect the finish on the bar) leaving about 28mm protruding from the chuck. Using VERY sharp tooling turn down the end for a length of 26mm to a diameter of about 4.05mm, the last job with the cutting tool is to face the end closest to the chuck, these corners must be kept really sharp and if need to be deburred use only very worn emery or fine steel wool.
Finish down to size with fine emery (if you look at pic 9 they look rough as old boots but in fact they are totally smooth like the one laying horizontal).
Now remount the rod with the 4mm end in the chuck (again protect if possible) with enough of the 4mm end protruding so you are able to get your measuring device on comfortably, as in pic 3. Now very gently face off the end until you get to your measurement in pic 1.
While still in the chuck get a felt tip and mark off 3.5mm in from the end of each spool face. If you look at pic 4 it shows my spools marked up and in the background are two grooving tools of the type I used, you could use a right and left turning tool if you are careful. The land between the two spools is not critical and can be any size from 4.5mm to 5mm, and the surface finish just isn't critical. Push the large end of the rod right up to the chuck to give as much support as possible and rough out between the spools to the marks you made as in pic 5.
Remount the spool again to have it protruding for getting in with your measuring instrument as in pic 6 and very carefully face the end of the spool until you reach the 3mm required. Push the spool you have just done right up to the chuck and carry out the same on the spool at the other end. Deburr as mentioned before. The spools are now finished, now just have to put in a steam transfer port.
The hole for the steam port is drilled just below the bottom port face, see pics 7 & 8. Make sure you don't touch the edge of the bottom spool and touch on with a small centre drill to give you a drilling detent, then drill right through with a 1.5mm drill, turn the spool thru 90 degrees and drill another cross hole the same size. Carefully deburr the holes and you should now have finished spool valves as in pic 9.
It has most probably taken longer to write this post than actually make them. I would like to thank Sandy of ACS for the design of this type of spool valve, it has saved hours design time.
Next time we will be making the bits to join the spools to the eccentric.
John
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I'm going to have to read that little lot about a dozen times to really start to understand it!
I suppose it doesn't help that I don't have a clue how these things work, but no doubt that will become apparent as we move through the next stages?
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Hi Eddy,
The way I wrote the last post was supposed to make it easy, just follow it step by step and you should end up with a good spool valve.
The easiest way I can explain the operation is that the two 3mm wide bits (the spools) act as small gateways, blocking two holes, one to the top of the cylinder and one to the bottom. The eccentric to which they are connected say moves down, because there are two they open two holes at the same time, the top one say lets steam into the top of the cylinder so pushing the piston down, while the bottom spool at the same time connects from the bottom of the cylinder to exhaust. As the eccentric moves thru 180 deg it then does the opposite and lets steam into the bottom and connects the top to exhaust and because there are two cylinders at 90 deg apart there is always a cylinder on power stroke and because of this the engine should always self start and run in reverse if the inlet and exhaust are swapped over.
Now you have gone cross eyed do you really want me to carry on, or will you just believe me that it works.
Just a little update on the monster that is running. It has now been on air for over 10 hours and hasn't missed a beat as far as I know in this time, I check every hour and it is still running. I have fitted a restrictor in the air line and it ticks over very slowly indeed, and it runs better in one direction than the other which suggests the timing is out. I will finish the runs tonight and carry on with building a speed control for it.
BTW still couldn't upload vid. says your box hasn't enough room even though the vid is only 15mb.
John
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That helps a lot John, thanks.... At least I now understand the basics of how the valves work.
I'm sure my grey matter will figure out the finer points as it comes together. If not I'll ask! :)
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Does ths help at all
If you click on it it runs
Peter
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Hi Peter,
As they say about a picture. That explained it a lot easier.
Its nice to get input from other people to help me out or even prove me wrong, or hints and tips, it helps everyone
Thanks
John
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:D :D
Hi PD's
John: - :great work my friend, you can be proud of yourself.
Just a little update on the monster that is running. It has now been on air for over 10 hours and hasn't missed a beat as far as I know in this time, I check every hour and it is still running. I have fitted a restrictor in the air line and it ticks over very slowly indeed, and it runs better in one direction than the other which suggests the timing is out.
There are many reasons for an engine to run slower in one direction than the other and, certainly, valve timing is one of them.
Another, and a very important one, is.... steam/exhaust passage port dimensions... specifically the cross sectional area.
I did a few quick sums on your ports John and I would like to suggest the following: -
Your main steam ports are 3mm dia = 7.097 sq mm cross section area.
Turning to your PISTON VALVE (Spool valve as you call it).... a couple of changes would be beneficial.....
1, The bore through the valve( to feed steam to the bottom port) is 2mm dia = 3.161 sq mm cross section area
This bore should be increased to 3mm dia.
2, The 1.5 mm cross hole has and cross section area of only 1.935 sq mm
so, since this goes right through, this would total only 3.87 sq mm.
Increase this cross hole hole size to 2.3 mm dia. (4.1 sq mm cross section area x 2 = 8.2 sq mm total)
In order to accommodate these changes the reduced dia (4mm) will need to be increased to 4.5 mm or the wall thickness may be a little thin.
In the cross hole area, and to avoid changes to the bottom gland, the increase in dia need only be long enough to accommodate the cross hole... the rest can stay at 4mm, hopefully this will still leave length to allow the spindle through the gland and with enough length for movement.
OK... if you think about what is happening... when the piston valve moves downwards, thus opening the top port, then the steam has direct access to a 3mm dia port.... on the other hand, when it goes to the top of its stroke, uncovering the bottom port, then the steam must first pass through the restricted centre bore, then through the restricted cross holes, before it gets to the 3mm bottom port..... QED less steam in a given time.
When you reverse the ports (for reversing) then the steam is entering via the centre area (between the spools) and has equal access, and ample cross sectional area to move through... thus no restriction to the incoming steam.
A similar issue occurs with the exhaust side if you think about it... and the same really should apply as far as port/passage cross section area.
Incidentally, making the reduced OD 4.5mm instead of 4mm will still give approx 13sq mm cross section area between the spools... so no problem here.
One thing I forgot to mention, when I sent you the valve info John.... the piston valve should really be lapped into the bore to give a very close running /sliding fit since this is how the steam is prevented from bypassing the spool and disappearing up the exhaust... tricky with a blind bore... I agree.
This type of valve was developed for steam locomotive use, and the full size ones are hollow to permit steam transfer between the ends, however, they are fitted with sprung rings to seal the bore.
Ok John... thats my 1 pence worth.... hope you find it helpful.... just observations and suggestions. :respect :respect2
Eddy.... the next installment of the STEAM AND STEAM ENGINES series will contain a complete section on how these valves work... along with lots of diagrams..... It is on hold at the moment whilst I get the galley finished..... not going a well as hoped :rant :hammer , but then does it ever?
Best regards to all.
Sandy. :computer :sunglasses
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Hi Sandy,
Many thanks for your input, its nice having someone on the team who is a specialist in this field. As you know, I make things to work and put fixes in along the way. This afternoon I will try your mods on a spare valve I have made and make the adjustment to drawing and prose to suit. I think that the 2.3 dia at the bottom should be meaty enough around there to do without changing the diameter, but I will reassess when I have carried out the mods.
The valves were tight in the bores as was and I lapped them in with a bit of t-cut (not as coarse as metal polish) and I have no leakage to talk about.
Many thanks for your input yet again, with all this help we should get a very good running engine.
John
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Mods all done, except rather than 2.3 hole at the bottom I have used two cross drilled at 1.5, 90 deg apart. This only gives a slightly lower reading but it does allow it to be modded without having a larger diameter.
I took the opportunity to seal the engine up whilst doing these mods so all packing glands are packed and piston rings are in, all mating faces are Hylomar sealed, no leaks at all
Now to the results.
Tried both directions, now both the same operationally even down to the raised tickover (but this is due to the engine being tight because of rebuild and rings). The speed is unbelievable on 40 psi, much faster than my oscillators, I think this must be because of a slight increase in efficiency, and maybe a little less friction.
So Sandy, you were right yet again, I am running out of thanks very fast.
Vid of modified engine - http://www.youtube.com/watch?v=I8UCWr_BeqE
John
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The new video looks good John, it's starting to sound like a little sewing machine - Perfect! ;)
I have to say that for a very basic engine that (almost) anyone could build with fairly simple equipment, it looks very impressive!
I can still see that next year could see me in the market for a secondhand lathe and other odds and ends!
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Glad you like it, but it still isn't finished.
Hopefully two or three more posts will see it done.
Hit a bit of a problem yesterday, came to get all the junk and bits to make the speed control and the o-rings I thought I had, I hadn't. So ordered some from my supplier - http://www.blackgates.co.uk/body_index.html
they should be here today or tomorrow, then I can carry on.
Will be posting sometime today about the eccentric straps & related bits as shown in the pic.
John
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:D :D
Hi PD's,
Just a quicky.... got to go and do more KITCHEN UNIT assembly..... :twisted: :rant :sob
John,
Happy to assist with a few small suggestions that may/would improve things, so no credit due my friend, you are the one that must take all of that for your great build. :respect
My input is given, in the true spirit of PD's, i.e... one modeller helping another.
I must admit, I never thought of using 2 crossed holes of 1.5mm, :thinking "silly old Scotsman".... :hammer .
I took a look at the video on U-Tube, however I am unable to get a very good viewing, very jerky and broken up, I believe this has more to do with the STEAM computer at this end though, but it served to show the beast in action.
One point.... now that you have fitted the piston rings and steam glands.... don't run the engine to much on compressed air, since this is very abrasive and the o-rings will wear very quickly. Better to run on low pressure steam, with a suitable displacement lubricator in the line... these also don't work on compressed air.
Best regards to all.
Sandy. :sunglasses :computer
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Sandy,
Thanks for the reply.
When running on air I always fill up the engine with diesel multigrade by injecting into the airline just downstream of the engine at least once an hour. I have to pull you up on the use of a displacement lubricator with air, my compressor produces so much water it is like running on cold saturated steam anyway (just joking of course).
With this post I should be up to date with the build.
The two sketches show what is needed to connect the eccentrics to the valve blocks.
They look complicated but as usual I think that this is my sketch that is causing the problem, if you refer to the pics all becomes clear.
Pic 1 shows the block sizes required for the eccentric straps. You will notice that there is a measurement change on them. These pictures were taken before the large holes were bored. I actually lost two of these sets because my boring was very slightly out and I broke into the joining screw holes. So I increased the width just slightly to give a bit more room for error.
The corners of the top blocks are removed purely for cosmetic effect, it will make no difference if you leave them on, but they will look a lot more bulky.
You will see on pic 2 that the plates are screwed together. Mark them up so that they stay as pairs and always go together the same way. Tighten them up really well and put on a flat surface and welly them with a gert big yammer an' a bit o' protective wud, to make sure they are nice and flat toogever.
Now measure your diameter of eccentric at the bottom of the groove, as in pic 3. Mine were all the same at 13.95 (I had used the same setting on the lathe for the depth of all of them). This worked out perfectly for me as I wanted 0.05mm running clearance. So this gave me 14mm exact. I don't have a 14mm machine reamer so the thought of boring six holes didn't enthuse me at all. Then a bright idea hit me, remember a bit back about the step drills I bought from Aldi. One of the sizes was 14mm. So out with a bit of scrap plate and duly wacked the drill thru. 14mm exactly, not 14.02 or anything else. 14mm bob on.
All six holes were drilled in less than ten minutes, all spot on, except for the fact I had drilled two slightly off centre and broke into the screw holes, so it pays to make a couple extra, just in case.
So in pic 4 you end up with half the metal gone. On the sketches it isn't too clear but there are two holes in the top of the plates, one (3mm) is for joining to the joint block and the other is an oiling hole for the eccentric, and thru use it has shown to work very well.
The joints don't need much explanation, just make as is. One thing you might like to try is to cut the 4mm wide slot in a slightly wider piece of metal then bring it down very gently to 1mm either side. The reason for this is that unless you can support all the side to full depth it will spring apart at the top of the cut and you will end up with tapered width sides. Even if you do get full support, when you take it out of the vice it will spring apart. A little later you will be silver soldering the length 2.5 screwed rod into the top of this fork, after the rod is screwed to the bottom of the tapped hole. After soldering the fork will be soft, just put the matching block into the slot and GENTLY squeeze together in a vice, this will realign the sides.
On pic 5 it shows the blocks joined to the eccentric straps. This is done by silver soldering (I will go into silver soldering maybe on the next post, some people think it is a black art and expensive, no such thing, just wait and see) the 18mm tube or rod between the block and the strap (after it has been fed into the two holes). What I did to stop it all falling apart before soldering is to squeeze the tube at the ends in the vice to make them slightly oval and tight in the holes, this will also give the required joint width for the silver solder to penetrate correctly,then put the assembly on a flat surface and get the strap and block level on the same plane. I will explain why I used brass tube (or rod). This is to give me a bendy, twisty, straightening fiddle just in case your measurements when you make the top and bottom parts of this engine were just not quite spot on. For a short time after silver soldering this tube will be fairly soft and can be fiddled to get this top block perfectly in line with the fork which is attached to the bottom of the piston valve rod. I didn't need any on mine, maybe I was lucky.
The design of the joining pin is the same as the one used for joining the conrod to the crosshead but slightly smaller. I designed them this way because bolts have a nasty habit of tightening up by themselves, and if this was to happen it would lock up the forked end, you can drill right thru the forked end and put a bolt thru but you must make sure that the bolt is free to rotate, has a smooth portion as a bearing surface and the nut is locked.
Now onto the second sketch, which shows hopefully all the dimensions required. As for the glands used on the piston rods, they are made in the same sequence. The screwy in bit is made first, then the bottom bit of the top bit is drilled and tapped. The two bits are assembled and the 4mm hole is bored thru them both (keep as matched pairs). Then the top bit is parted off, the screwy bits are put in the chuck and the top bit of the top part is turned to fit the piston valve hole. Two mounting holes are drilled in the positions as shown.
This brings us onto pic 6. The reason for only two mounting holes is because of all the cross drilled holes in the block it will be attaching to. Look at the pic and it shows the position of the two screwed holes. Stick as previously done to the bottom of the valve and spot thru with a drill. These holes can be drilled until they penetrate the cross drilled holes used for mounting the piston block to main block, and tap out to 2mm.
So now you have all the bits to assemble and run this engine if you want to, and this is as far as I have got. The next post will only be a small one, about making flanges and silver soldering. If I have got all my calculations right we will only have to bend one little bit of pipe, the rest will all be straight (like the ones Derek picked me up on before).
I suppose you lot will also want a displacement lubricator as well (get your tiny drills ready).
John
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Sandy,
Here in Oregon, live steam is not allowed at model shows and most all model steam engines are run on air. To combat the lubrication problem I placed a 1/4 pipe T in the air line. To the top of the T I installed a drip oiler.
To prevent the air from blowing back into the oiler I soldered a piece of tubing, in the end of the inlet hose fitting, so that it extended past the bottom of the oiler. I drilled a very small #60 hole in the tube just before the oiler just to allow a very little air to blow the oil into the main stream. I thought about building a vortex but was afraid it might suck all the oil out of the oiler.
Bill
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I have been looking at the pipework and came to the conclusion 1/8" pipe would be a little restrictive in the bore, so have decided to use 4mm (5/32") instead. But this entailed a redesign of the steam flanges plus a change of material to give the strength to couple it all together, and of course I designed the control valve around the smaller pipe. So sorry no posts for a couple of days at least.
And I was hoping to get the whole lot finished within the next week :oops
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I will be splitting this post about the steam flanges over two posts, the main reasons are that there are a lot of small operations to be done and the other reason, I haven't totally finished the machining yet.
I will post the sketch on the next one because there are so many pics to get thru.
First off is what we want to avoid, pic 1 shows the dreaded bent pipes and the little machine you use to do it. If you haven't got one of these, doing pipework can be a bit of a nightmare. If you want to make one, I can help, PM me, this one only took about half a day but really requires, unless you are a great tool grinder, a rotary table with a mounted chuck.
The good news is that I have now got it so that no bends will be required at all.
Picture 2 shows the reason for the delay, the brass flange, because of the thin wall on the waisted portion just wasn't strong enough to take the rigours of machining and I didn't think it would be able to support the weight it would be carrying. So I have decided to make them out of a space age product called EN1a, otherwise known as free cutting mild steel, obtainable everywhere and CHEAP.
Because I didn't want to be continually changing tooling, I decided to set it up like a production line, so I cut off billets to make one on each end and the bit that was left from the middle would make the second type of flange required. The billets in the pic have already been turned down to 12mm diameter and are about 45mm long.
Pic 3 shows turning one end of the bar down to 12mm long by 6mm diameter, once one end is done, turn bar round and do the other end the same. Do this until you have enough for your engine, 4 required but I would make 6 just in case.
The next op as shown in the shaky pic 4 is to turn down a waisted portion for 7mm long by 4mm diameter,using the same method as was used for the spool valves. The diameter of 4mm is fairly critical, too much larger and your bolts won't fit, any narrower and you will be weakening the structure of the flange.
The components in picture 5 is what you should end up with at this stage. The end marked in red is a reject that will be discarded. In the background is a little book called a ZEUS book. If you are doing any machining especially if your are making metric bits on an imperial machine (as I do) or vice versa, this is an instant help, because it gives you direct conversion charts plus loads of info like drill sizes for tapping etc. I use mine all the time. I've had this one for 25 years and is getting worn out, but being so tight I don't want to shell out the £4:75p that a new one will cost. Buy one now if you haven't got one.
There is no picture for the next bit, but all the operation is that each part is parted off, and the flange ends machined to a thickness of 2mm, DO NOT DRILL THE MAIN HOLE UP THE MIDDLE YET, if you do the part will not be strong enough to go thru the next machining procedures. The bit that is left from between the components is used to make the 3mm thick plain flanges, that takes us onto pic 6.
Rather than boring out the soft jaws I use on my chuck I decided to make a split bush to hold the small discs. All this is is a piece of soft metal that has a thru hole (I made mine 9mm). Then bore to a depth shallower than the component part to a diameter where the part only just pushes in. Then mark one of your jaws with a marker and physically mark the bush adjacent to this jaw. Now mark the bush at a position half way between two jaws. Remove the bush from the chuck and where you marked between the jaws cut all the way thru with a hacksaw or bandsaw. Clean off any burrs, put your component into the bored bit of the bush and remount into the chuck, aligning the mark on the bush with the marked jaw. You can now face and drill to your hearts content, as long as you always realign the mark on the bush and chuck jaw, all should be ok. Discard the bush after use because it cannot be rebored to use again.
You should end up with what is on the last pic. These took me about 3 hours, being new to it if you can make half this qty in that time you will be doing well.
John
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Hi PD's.... & John says
'pic 1 shows the dreaded bent pipes.... If you haven't got one of these, doing pipe work can be a bit of a nightmare' ....well I do agree with this
'and the little machine you use to do it' & I do agree with this too
Well...PD's... the real point here is that the design difference of the tube bender set produced by John & the set of Dub-RO American tube benders I purchased
Johns version will display roller to roller clearance 0.0005" [1/10 of the thickness of a sheet of A4 paper I posted to John] & the true U shaped valley in each roller would be 0.0625" depth...+0.0005/- zero
The roller set in my Dub-RO has 0.002" clearance between rollers so my 1/8" bends in brass have a convoluted effect & subsequent thinning of the wall thickness off axis :rant
My Dub-RO set for 5/32" od tube is """"better"""" & the degree of convolution is greatly reduced
Having said this...my latest plan is to use my version of "DUO-Core" but in brass tubes :hehe .....
1/8" OD brass tube soldered with COMSOL within 5/32" OD telescopic brass tube... then bend :hammer :hammer the DUO-Core tube set & :great
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I gather from your post Derek is that you approve of the tube bender.
As promised here is the sketch, I think I have got everything on there.
Picture one shows the flange base being drilled. Centre the flange to the chuck and use machine offset to locate the two 2mm mounting holes.
Once you have the two mounting holes you can then do as I have done in pic 2. Put two pieces of rod thru the holes and locate them down to the top of the vice, then machine down 2mm. Turn it over and do the same to other side. Be careful, only nibble away downwards not from the side, otherwise it WILL lift the piece out of the vice.
In pic 3 I show that I have used the flange face resting on a parallel to keep the hole square to the flange. First I centre drilled, then went down with a 3mm drill to a depth of 4.5mm, then followed up with the 4mm required to the same depth. This is the stage at which the brass flanges failed, they couldn't take the pressure applied by the vice and duly buckled.
After the last stage, remount into the lathe and drill up the centre of the flange with a 2.8mm drill( the internal size of the copper pipe) to join into the hole for the pipe at the top.
Picture 4 is how I get bent tubing straight again. The annealed tube is rolled like a using a rolling pin between two hard surfaces.
Make sure your copper tube is squared at the ends and deburred on inner and outer faces.
All the finished bits are shown in picture 5, for the copper pipe you will require 4 off 4mm (5/32") by 30mm long, one off same diam by 60mm long and one off same diam by 90mm long.
In pic 6 it shows all the bits assembled for silver soldering. I need to point out here that for silver soldering to work correctly the parts should NOT be a tight fit together, there must be a very slight gap for the solder and flux to penetrate into to form a good joint. If you use a 4mm drill for this pipework all should be ok as 4mm is very slightly larger than the 5/32" pipe being used. The way I get the bits to hold together while handling is to slightly flare the end of the tube, so that the tube is held in the hole by the flare but still allows solder flow.
To put my mind at rest I silver soldered one of the rejected parts after drilling the main centre hole in it to a bit of copper tube and tried to break it by putting the flange in a vice and using mole grips to try to put enough force by twisting the pipe to break either the waisted portion on the flange or the copper/steel joint. As you can see in pic 7, I failed miserably on both counts, but at least it proves that the flanges are strong enough.
Just a word about failure rate, I started to make 12 flanges, one was rejected after turning, one was used to set up the drilling stages, the third got damaged during drilling because I hadn't tightened the vice enough. That is a 25% attrition rate, so always make a few spares.
Next time, a post about silver soldering, then onto the control valve , which I am just making and proving.
John
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I wanted to get this out of the way so that I can concentrate on getting the control valve done. These only came out of the pickle bath an hour ago.
SILVER SOLDERING
A lot of modelmakers think that silver soldering (from now on SS means silver soldering) is a black art that they try once, make a mess of and don't do it again, or just think it is too expensive to gear up for.
I will tell you now, I am tight as a ducks a**e, and that's watertight when it comes to SS, once you have the intitial bits the running costs are minute. I showed on the last post how strong the joints produced by correct SS can be, many times stronger than soft soldering or glue.
Now I will refer to the pics of my bits and bobs.
Pic 1 is my collection of soldering things, I do have a proper home made brazing hearth but it was too heavy to set up here, and you wont need one anyway. The last time I used it and the big propane gas torch shown here was when I made boilers a few years back. The ones connected to disposable cans are a standard plumbers blowtorch, which I use for the large bits, and a can adaptor to allow me to fill the two small blowtorches with butane/propane mix.
The little orange one is what is now called a 'Chefs' blowtorch is what I use the most, while the little pencil one I used to use for building railings while they were still attached to the model boats.
The next bit in the lineup is my 'mobile SS hearth', in other words a couple of firebricks from a builders merchants, if you go there and ask if they have any broken ones they might even give them to you. DO NOT use household bricks, when they get hot small bits can shatter off them and fly in all directions. I use this all the time and move it about my workbenches to where needed, as long as you don't get them too hot and keep away from flammables they are ok.
The big bucket is a recycled (nothing goes to waste) popcorn bucket that is filled with my quenching water and is normally next to the mobile hearth. The one on top that looks like someone has piddled in is my acid pickling bath for removing flux and for cleaning the pipework. The contents of this is explained in the next paragraph.
The items in picture two are now going to be explained in an easy to understand manner.
Steel wool, this is used to clean the parts before joining. Any oil or grease or sometimes even fingerprints can stop the joining of metals with SS. So degrease first, then a rub over with wire wool (cabinet makers if possible, some others are treated with oil to stop it going rusty), then assemble the bits together. Be careful with wire wool around heat, it catches fire very easily and is usually a pig to put out.
Citric acid, used to be able to get this anywhere but now only readily available from chemists. When you go in, go in filthy like you have been under a car for a week and explain to them that you need it to make a pickle bath for soldering. You will get some weird looks and whispering between the staff, the dispensing chemist will usually be called to have a word with you but as soon as he sees how filthy you are he will let you have some just to get you out of his shop.
The reason for this is because citric acid is a main component in the use of heroin based drugs. We use it as a pickling bath and I mix it about four teaspoons to half pint of water. In a sealed container I find it lasts for many months, and I only throw it away when the things growing in it get to look a bit dangerous.
The thing next to it marked flux does in fact contain, yes, you guessed it, flux, but in an emulsified state. It normally comes as a white powder, and should be mixed with water to a consistency of thick cream. Again I find that putting it into a small sealed container (film canisters are ideal) it will keep for months, just stir it up just before use. The purpose of flux is to stop oxides forming on the surface of the metal and clean at the same time, allowing the SS to bond into the surface of the metal.
There are many types of silver soldering fluxes but I would go for one of the tenacity ones. I use tenacity 4a, which is really for stainless steel and is fairly aggressive, or the most popular of its type is tenacity 5, designed for use with normal steels. What these fluxes have over the other general purpose ones is that they can still do the job of cleaning the metal at much higher and prolonged temperatures than the general purpose ones, but as I said before they are slightly aggressive and need to be cleaned off before it thinks your copper pipe is muck and starts to eat it away.
It is just applied to the local area to be joined with a small brush.
Next we come to the most confusing bit, the silver solder itself. It comes in all shapes and sizes, melting points and even as pastes (but these do have a fairly short shelf life). The reason for the different temperature ranges is to allow multiple parts to be SS onto a construction at different times. You would use a high temp one to begin with, then with each subsequent addition you would use a lower temp than the previous one. But for our purpose we will stick with general purpose or bogstandard easyflo.
Most people go for the 1.5mm rods costing up to about £3 per rod, and end up filing most of it off the job they have just SS. It is just too large for what we want to do. I use 0.5mm silverflo wire, as you can see it costs 82p for a 3 foot length, and would do all the joints on at least ten of these engines, for slightly bigger joints it also comes in bigger sizes.
You will notice at the front of the pic are what look like springs, they are in fact coils of SS wire. I wrap the wire around the next size down of tubing that I will be using, and about 2/3rds of one coil is enough for one pipe joint.
Onto pic 3. On here I have assembled the parts and put one coil onto each joint, all that is left to do is paint a small amount of flux around the joint and stick some heat onto it. You will notice that I have protected my table because of the flux.
It isn't worth taking pictures of the process because the time you reach the temperature it is all over but I will explain the principle.
If I was doing one of the stand off flanges, I would start by heating up the flange itself to a very dull red, you can only just see the red, at this point the flux has dried up and started to turn to a liquid. Because the copper is a better heat conductor than the steel I will let the copper take its heat from the steel so I will move up towards the joint, as you do you will notice that the flux is cleaning the area and all of a sudden the silver solder will melt and flow into and around the joint, once this stage has been reach take away the heat, if you reach a distinct bright red colour, you've already overcooked it.
Pick the bit up with a pair of pliers (they get very heavy if you use your fingers) and drop it into the quenching water. This will knock most of the flux off, but to do a good job transfer the bits to your pickling tub, I have left bits in this for more than a week and they were still ok when I took them out. A couple of hours usually does a good job. One point to mention, if you are SS silver steel or any of the high carbon types, let the article cool down before dropping it into quenching water, otherwise you might find the component has gone glass hard and very brittle.
Now onto pic 4. Here are the bits straight out of the quench, you will notice on the standoff ones especially the bright silver area on the steel and the clean area on the copper above the joint, this is the flux doing a great job.
You will notice no big blobs to clean off, just nice clean fillets. Just a quickie pickle and polish then ready for the next stage.
Piccy 5 is out of the pickle after an hour, and just started to clean them up.
Not a very good pic 6 but you can see how this method produces lovely fillets with absolutely no wastage, and very little clean up, just a quickie polish and they are done.
And now one for Derek, here he is back from uni with a new degree under his collar (excuse the pun) trying to get me to make the next bits, so won't be back until its done and dusted.
John
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Hi PD's & thanks John for this......from my trials [see attachment]...I think I was suffering 2 or 3 faults :rant & poor results.......
1) I should use more air cored brick work to support & minimise heat loss
2) maybe preheat the complete tube set with the larger Primus gas torch
3) use a pickling solution over & above the BORAX flux paste
4) use 0.5 diameter pre formed rings of S/S as you have done over the 1.5 diameter wire trialed
5) use the smaller blue hand held small gas burner for final S/S melting
Will trial the revision this weekend if I can get the 0.5 wire locally & so I say to myself... :luck
Oh BTW...please offer my hearty congratulations to the DOG....he looks so pleased :hehe
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Hi Derek,
By the picture you have a few problems here.
You do really need real firebrick (the type used to line firebacks), it doesn't take the heat away but keeps it very local, in fact when you are doing something larger the bricks glow bright red around where the heating is taking place. The size of pipe you are doing there can easily be done with the little blue torch you have there.
By the look of the deposits of black on the brick, suggests you are using a carburising flame. The black you see on my bricks is caused by twenty years of use. This is caused by not enough air in your gas mixture, check the air supply holes around your nozzle to see if they are blocked, sometimes the nozzle itself can be knocked into a bad position, if the nozzle has a securing screw on the outside, slacken it off and try sliding the nozzle back and forth until you get a nice bunsen blue area in the centre of the flame. The tip of this centre cone is the area of maximum heat, and this is the part of the flame that is used.
From the look of the workpiece the flux just isn't doing its job. There should be nice clean areas around the joint, as I showed in my post.
It might be you are taking too long in heating up, and killing the action of the flux, that is why I use an aggressive type flux. For small jobs like this, if it isn't all over and done with in ten to fifteen seconds you are most probably cooking the flux.
What you can do with your silver solder rod is give it a real good going over with a hammer until it is very thin and cut off a very small piece and place on the job, it just might be the big rod being put onto the joint is soaking away what heat you have there.
Hope this helps for your search of the perfect joint (for medical reasons of course).
Bandit the dog says thanks, cat says nothing, even to me.
John
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Hi All,
I forgot to mention in the post about the stand off flanges about drilling them out. As the tubes were silver soldered into the flanges, the end of the tube protrudes inside the steamway. You need to run a 2.8mm drill down to cut off the end of the tube inside to allow full steam flow, be careful you don't drill all the way thru, you only need to take off the first bit of tube you come to. Put a drop of milk down to act as lubricant otherwise you might break off your drill inside trying to cut the very soft copper.
I have included this time a couple of pics to show how far I have got with the steam control valve, doesn't look much, but trying to get all the holes missing each other inside and also making it fairly easy to make took a lot of working out, hence the delay.
I have decided to use the main block and the two piston valve blocks to act as jigs while it is all soldered together, so really all this needs to be done before engine assembly, I am lucky, I have a second set of parts I can use.
The reason I have done this post is to show how close we are to finishing and because of medical problems I am having to take a few days out of the workshop. I can still answer posts if you have any questions or comments, but I won't be doing any machining.
John
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I had forgotten that I had a few pics left in my camera, so I have decided to make a post out of these.
The blocks need to be made and all completed before I could carry on anyway, because the bits that fit to it have to be lapped into the main bore and the soldering has to be done first just in case we get a little bit of distortion in the main bore. I suppose you could bore it after soldering but it might be a bit difficult to hold well enough.
The sketch shows all the positions and sizes, thru a key. They are drilled in a specific order, and that is shown in pic 2.
Pic 1 shows the size of blocks required. I have stated that these can be made out of brass or steel, preferably brass (a lot less hassle to drill and tap).
Just a quick warning when you come to bore the main hole, when you are putting the larger drills thru to get to size (over 9mm) you will start to hit the bottom of the four holes drilled on the centre of each side, take it very steady. Also I would recommend drilling the 4mm tube holes from each side rather than deep drilling all the way thru. Another thing to point out is that the 3mm holes that these pass thru, have to be sealed on the outside of the block, this will be shown how to be done later.
I also have some pics left of silver soldering the control block to the pipes, so I might make a post out of that, just to pass the time until I can get active again.
By the way, this engine is starting to look a bit battered, maybe caused by being the prototype and has been taken apart more times than I care to remember, hopefully the other will look a lot better.
John
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Going back to silver soldering for a minute.... You mentioned using citric acid as a pickling solution John. I assume anything that is acidic will work, so what about something easier to get hold of such as acetic acid (vinegar)??
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Eddy,
Never tried it, except on my chips.
What I do know is that when I used to visit a plating shop, they had pallets of rotting oranges and lemons hanging about the place, these were being used for the same process as we are doing, cleaning.
All I really know is that I have only ever used citric acid, and it works, and works well.
Sorry I couldn't answer your question any better Eddy, all I would suggest is try it, and see what happens. It might even get the steel to come out clean, as with citric acid, coupled with the heat process I think, or maybe a chemical process with the flux and copper, steel comes out with a lovely chemi black finish, seems a shame to clean it off back to polished steel.
BTW, citric acid is not difficult to get hold of at all, just tell them what you want it for, and you shouldn't have a problem. Just buy a couple of boxes of it and it should last a few years, as I do.
John
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Hi PD's ....in OZ, my local Pharmacy...they said no worries Derek.....we know you won't use it for DRUG related work :hehe just AUD$27.00 for 500 gms of Citric Acid ... :rant & :sob .......then I presented the Citric Acid photograph from John with the container....50 gms for UK 60 P........smart ar#e Pharmasist suggested I could purchase a lot of Citric Acid for the air fare to UK.............so :thinking ....I drove to the local Home Brew shop :beer & :news .... a new unopened 1000 gm bag of Citric Acid white powder
I purchased 100 gm of Citric Acid for AUD $3.40 :towel
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Good on you Derek, that showed 'em. Mix it with a lot of water, add a bit of sugar and we're all coming round to your gaff for a barby and nearly lemonade. :beer
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Here are the last pics I have got, it shows how I soldered up the steam control block.
First off is sealing up the bit of the transfer holes that aren't required. I tapped the the outside bit of the hole 4mm and screwed in a bit of brass threaded rod, you can just use a bit of rod if you want, or even make a feature of it by turning up a little cap with a spigot on it, your choice. I use screwed rod to stop it falling out in subsequent reheating. Don't block the steam transfer holes with the plugs.
Picture 2 has the block, mounted to the assembled bits of the engine so it acts like a jig to hold everything in place, without it you would end up with a real mess with nothing lining up, the bits of the engine will get very little heat onto it. Don't forget to centralise the block on the pipes so it looks nice and neat.
As I assembled it I put a bit of flux onto the pipe ends, also notice that I have used about 1 1/2 turns of wire, this is because the pipes penetrate a fair way into the block, really it needed two turns as the fillets are fairly small on the finished block, but they were fully sealed, which is what we are after.
Now the heating up bit. Because it is a fairly large block, I used my plumbers type torch, the one with the screw on can. All I did was to play the torch onto the area between the big hole in the middle and the outer edge of the block in a rotary motion until I just started to see a faint tinge of red then just play the flame onto the block at each corner until you see the solder run. All done in 20 to 30 seconds. There is no easier way to describe it, just don't play the main part of the flame onto the pipes as you will cook the joint. Then put the whole lot into quench water.
This now brings us to piccy 3. The block has been taken off the 'jig', you can see that the flux has done its job keeping the soldered area clean, and because the heat was kept directly off the pipes the joints on the flanges are totally untouched. The solder around the plugs has remelted but they still have a good seal.
You will notice that the 'jig' has what looks like a burn mark on it, in fact all it is is a waxy like substance that just wipes off with a cloth, I think it is just a bloom caused by flux vapours. Notice all the good joints. I remeasured the main hole and there was no detectable deformation, so looks like we are in with a chance of making a good valve, Just got to wait until I can get the bits made.
The last pic is the assemblies after an hour in the pickle, looks really bad, but a wipe over with steel wool brings it up just like new.
By the way, both these assemblies fit both of my engines perfectly, they are even interchangeable, so the 'jig' worked.
John
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Morning PD's.....John....when we look at 'sketch for steam control main block.jpg'.... in the listing Faces C & D.....
the drillings C2 for the 4 mm tube... are these not shown in the following 'all holes drilled ready for joining .jpg' as being pre drilled with a healthy chamfer :?:
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Hi Derek,
You will notice that I always give all my drilled holes a good chamfer, usually because there is something bolted to the face and if not well chamfered it tends to hold off whatever is fixed to the face, and usually causes problems. But well spotted about the larger chamfers for the holes that are to be silver soldered, I forgot to mention about them, they are there to promote good penetration and a stronger joint. With you eagle eyed lot, I can't get away with anything.
To all following this lengthy build.
I know that this large assembly does look a bit daunting, but if you follow a few basic rules and a bit of practice I am sure everyone will be able to assemble it. If you really don't think you are up to it, if you can get all the bits to me by whatever means possible, with your 'jig' I will gladly build it up for you. So remember, cleanliness of the parts and a good flux plus don't overcook it are the keys to good SS.
Hopefully by the weekend I should be active enough to carry on with the build. There are only about 7 or 8 more bits to make and it is all finished. I have got to get mobile again, I have been asked today to display my engines in conjunction with the model boat club I belong to, at a steam rally in a couple of months, so I have to get going to get them all finished and prepared.
John
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Hi PD’s & sorry to post outside the forum…. but couldn’t get this attachment to link up……John …this is the 0.5mm diameter SS wire offered in OZ & that we have spoken about……66% Ag??????? sounds very high… I have yet to get confirmation of my order now for six pieces ….& the Easyflo flux – Derek
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
Silver solder wire easy .5mm per Mtr
- lowest temperature silver solder
Price per pack is $AUD6.60 or $US5.3
(other currencies click here (http://www.x-rates.com/cgi-bin/cgicalc.cgi?base=AUD&value=6))
(http://craft.ontheinternet.com.au/index.htm)
Post generated using Mail2Forum
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deleted ...Derek
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Hi Derek,
The stuff you have got there is absolutely perfect for general purpose silver soldering, like we are doing here, but definitely a little on the expensive side. I would mail you some by airmail and it would be a lot cheaper, but I don't know if it would be picked up by customs or anti terrorist agencies as being a suspect envelope.
I have just found this web site and although it reiterates most of what I have already said, does contain a bit more about the use of silver solder for larger fabrications like boilers.
http://www.pollymodelengineering.co.uk/global/technical-notes/basic-silver-soldering.asp
I think you are worrying a little bit over this, I always thought you lads were ready for anything, or is it the thought of opening your wallet that makes you sweat.
I know it does me, I did a few weight calculations yesterday about this engine, like on average two thirds of the material is taken off due to machining etc. and the cost of this engine will come to well below the ten pounds I originally said, that is of course because I use recycled bits from the scrappy. The fixings and bits of rod will most probably end up at around ten pounds. If you had to buy all the materials from retail sources, maybe the whole lot would come to less than £50, but you would also end up with most probably enough left over materials to build something else.
But you can't include your time, that is as I see it, many hours of pure bliss, enjoyment and sometimes frustration. But isn't that what doing your own thing is all about.
So don't worry about your SS, all of a sudden everything will click into place and you will be running round SS everything you can get your hands on.
John
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edited
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:D :D
Hi PD's,
Ok so I have taken a few hours off rebuilding the domestic galley...... what a diabolical job, it has fought back at every opportunity.... :rant :hammer
SS....... Derek...... If the wire you have has 66% Ag then it most certainly is not easyflo and will/may have a much higher melting point.... possibly in the region of 720 deg - 780 deg C which would also need the higher temperature type flux.... Tenacity No. 5 or similar.
A further problem with the HIGH Ag content types is their reluctance to flow around the joint, especially if the flux gets exhausted.
If you are SS brass tube with this stuff, then take extreme care as it will be very easy to melt the tube whilst trying to coax it to flow properly.
Easyflo has 42% Ag + 25% Cd + 17% Cu + 16% Zn and has a melting range of 610 deg - 620 deg C
The Cd content in this material makes for very quick and easy flow of the material, however, be very sure to keep the area well ventilated..... Cd is dangeroooossee.
Normal easyflo flux will be Ok for this, but not for the higher temperature stuff.
A good supplier for all SS products are to be found at http://www.cupalloys.com
They do a complete range of SS and allied products and offer a good mail order service.
A lot of useful info can also be found on their web site.
Alloy type 842 is the equiv. of easyflo.
Alloy type 456 is the Cadmium free equiv. with a melting range of 620 deg - 655 deg C.
John...... Engine progress looks great, with only the regulator block to go.
I trust the final episode will include your method for setting the PISTON VALVE timing?..... I know how to do it, and I am sure you do, but I am sure others would need some help on this...... NO PD's you don't adjust the eccentric position... this must remain at 90 deg. to the crank.
Best regards to all.... congrats to the DOG :no1 ..... ***** to the CAT :nah ,
Sandy. :computer :vacat :beer
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Hi Sandy,
I am leaving the timing of the engine to the very end.
Control valve is done and tested, not as great as I expected but it is a lot better than the disc type with two crescent slots.
I am at this moment making the lubricator.
Having a bit of trouble drawing at the moment but hopefully will be able to get everything together by tomorrow.
Here are a couple of pics of control valve.
John
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Have you got a picture of the innards of the steam valve please.Peter
ps
Great build
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Hi Peter,
Don't worry, just getting my hand working again, doing all the drawings today. So should be posted later.
John
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Here is the second part of the control block build.
This one is a bit of a long haul.
The major point on here is the recess for the 4mm bore by 1mm cross section viton o-ring (purchased from Blackgates Engineering).
This o-ring stops steam leakage thru the control arm hole. The recess is bored 0.9mm deep, refer to picture 1, to allow for an 0.1 mm crush on the o-ring.
This area can be machined to suit if you have o-rings of different sizes, but you must remember to alter the spindle size and the clamp hole size.
Anyway, back to the making and building, this is done in stages to allow the correct fitting of parts.
The first bit to be made is the spool. Turn your bar down to fairly tight fit in the main bore of the block, for a length of about 30mm. Then turn down the 15mm long by 4mm spigot on the end. Part off the spool leaving it about 8.5mm length on the main spool. All shoulders on this spool valve need to be kept fairly sharp and square, so no heavy deburring.
Refer to pic 2 shows what the spool should look like, and it should be fairly tight in the bore. Next hold the spool by the spigot of your chuck, and put a bit of metal polish, t-cut or chrome polish (raid the garage, you might find a very mild abrasive substance in there) and start up your lathe on the slowest speed possible. Refer to pic 3. Being very careful about keeping your hands away from the chuck ( I used my collet chuck because it is safer for me because I have to work left handed), gently feed the bore onto the rotating spool, get ready to let go just in case it galls up and starts spinning (galling is where the materials lock together, usually it is caused by the materials being the same or one is very soft). If this happens turn off the machine and try to unscrew the bits apart, if not remove the lot from the chuck and gently tap apart using a piece of wood to protect the surfaces.
If all goes as planned the spool will go all the way thru the block, move the block up and down the spool a few times and it should feel nice and smooth and free. Don't overdo it. Take out of the chuck and give everything a very good clean, you don't want abrasive running around inside your new engine. Put a bit of oil (I use multigrade or 3 in 1), on no account use WD40 anywhere near this engine, this was mentioned by both Sandy and myself a few posts back, it ruins certain types of o-ring seals, and put the bits together and turn them, they should be silky smooth with no rock between the parts. If you've got rock, you've either been to the seaside or you have overlapped the parts. Make a new spool and start again, don't worry about the bore, we make everything to fit that.
This takes you to pic 4, showing the bits together.
Put the spool away safe for now and refer back to picture 2. We now make the top and bottom covers. Start with the bottom cover, remembering from the sketch that this has a thicker flange to allow for threading to 2.5mm. The spigot on it is machined for a good fit in the bore. The top cover is like the spool, done in stages to keep everything in line. Turn the 7 mm spigot first and part off from your main bar.
Remount in your chuck by holding onto the 7mm spigot. If you haven't already done it turn down the od to 22mm. Now turn down the flange and the spigot for the bore, don't worry too much about the 1mm depth for the bore spigot, close enough is good enough, that goes for the bottom cover as well, as long as the total thickness of the flange and small spigot together add up to the total required on the drawing all should be ok. At this stage bore your 4mm hole. Next cut your recess. If you are worried about getting a boring bar to do this, let me know and I will show you how to do the job with a throw away one that only takes 10 minutes to make.
Now you have got your two covers, pick up the holes from the main block and drill and tap all the holes. Then go and have a coffee and or a fag, cos the next bit is going to take ages.
Now you are refreshed and remember how I told you to make the 10mm diameter spool longer than required. Put the spool in the bore, pop the bottom cover on followed by the top (no need for o-ring until final assembly), no need for bolts yet. Hopefully the covers don't touch the faces of the main block, if they both touch, make a new spool, just a bit longer this time. Put the assembly on a flat surface, bottom down and push on the block, this will seat the bottom cover and raise the top cover away from the block. This is the amount we need to remove from the length of the spool. Do a rough measure and remove a smaller amount from the bottom of the spool, try again, if it is getting very close, just remove 0.02mm at a time, until you are so close put a couple of screws in the covers and see if it still turns (don't tighten down until the later stages), continue until you can just turn the spool with the screws tightened, with no up and down movement. When you get very close, rather than turning any off, try emery on a flat piece of wood to just to remove minute amounts. It took me about twenty disassemblies to get them perfect. Now to hack out the slots in the spool
Refer to pic 5. The slot is central on the spool depth. If you haven't got a 3mm cutter a 1/8" will suffice. Cut down to 3mm depth. Before you take out of the vice, scribe a line parallel to your cut across the face of the 4mm spigot, this is to show you where the control faces are after it is assembled in the block.
Now go to pic 6. You have to mount the spool so your cut is parallel to the first one, I don't have a narrow enough parallel to sit inside the previously cut slot, so I improvised and used the blade on my engineers square. Machine the same position, size and depth of the first slot. Job nearly done.
Only deburr by slight scraping of the edges. You will most probably find that it will now not fit into the bore, but just put a bit more metal polish on to the spool, and do a very gentle relap.
Clean down again and assemble, using some sealant on the face joints, but this time put the o-ring in, this will cause a slight bit of drag but nothing to worry about.
Make the control arm, fit it so that it is at right angles to your scribed marks and you should have a non leaking control valve.
All the bits for the assembly are shown in picture 8.
John
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Almost there, the last component for the engine.
I have made here a fairly large lubricator, should get a good session out of this.
Three bits on the sketch, the fourth you have made previously, the longer of the two steam pipes.
Picture 1 shows the three parts to be made plus the long tube with a hole drilled half way along in line with the mounting bolt holes, the hole only goes in one side, mine is 0.7mm diameter, but you can use up to 1mm. If it underlubricates I can always open up the hole, but if it lets too much thru it is difficult to make smaller. The bit of text pointing to the cap is if the cap won't tighten down fully, just put a small recess to the bottom of thread depth and that should cure it.
The o-ring is 8mm bore by 1mm cross section viton (the same as the piston rings), the one shown here is in fact a used one from running in my oscillators, it is only worn on the outside edge so why pay another 47p for a new one, as I said before, nothing is thrown away until it can't be used any more.
Pic 2 shows the bits silver soldered up. I soldered up the chamber and top first, then put it in the lathe to be cleaned up, then I soldered in the copper pipe. When soldering this in make sure that the flange is in the up/down position otherwise you will have trouble filling the lubricator, but not emptying it. I put the hole on mine facing up, so if it does get blocked it can be cleaned out.
ONLY USE CORRECT STEAM OIL IN THIS LUBRICATOR. For the rest of the engine almost anything except steam oil or WD40. I use multigrade.
You might have to make a few extended tools to fit these two pipes correctly, but that is the price you pay for having no bends.
I will try to get the timing sorted by days end, but no promises.
John
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The final bit of the build, getting it to run efficiently.
First look at the photo, it shows the position of the parts I will be referring to.
It is easier to set up if the top and bottom are not joined at the start, as it is easier to adjust the crankshaft timing, but can be done with things built up.
First you have to make a decision whether you want the engine timed to run clockwise or anticlockwise as viewed from the flywheel end of the engine, it shouldn't matter, it should run the same in both directions, but due to machining errors it is not always the case. If it doesn't work well one way, try the other.
I have given you the view for both on the sketch.
To start, set the two cranks either side of the crankshaft centre bearing block at 90 degrees(or very close) to each other and tighten up, these will not be moved again.
Viewing from the lubricator end of the engine, set up No 1 crankshaft to a horizontal position as shown in the sketch, depending on direction chosen. Slacken off the screw in the crank nearest to the eccentric and turn the eccentric until the marked line (you did remember to put the line on) is at 90 degrees to the crank and lock up the screw. If you didn't mark the lines on you will have to use a DTI and find the point of highest lift and mark that.
Turn the engine round so you are viewing from the flywheel end and carry out the same procedure on crank 2 and eccentric 2.
That is the bottom end timed. From now on nothing should be moved on the bottom end.
Assemble the top to the bottom and carry on with the sketch about timing the top end. Leave the bore top caps off, and the piston valve end covers, but put screws or nuts on to hold the piston valve block in the operating position.
We will totally complete the piston 1 and valve 1 first.
Always turn your engine now in the direction you set the bottom up on, there should be no difference but you never know in this world.
If you read the sketch it explains everything, after you have finished the number 1 end, proceed to the other end and carry out the same procedure.
You should now have a fully timed engine. But because we all have different tolerances and fits no two engines are ever the same, so might need a little bit of timing tweaking on the piston valves, only minute, opening slightly earlier or later, but at least you can now always set to basic.
Mine was a fair way out all round when I retimed it today, but my vids show that even being out on that, the engine will still run fairly well. It took me about half an hour to retime mine, and seal the plates.
If I have made any mistakes on here please let me know and I will put it right.
John
-
Hi PD's.... still a brillant build John :bravo & you say.... made from scrap...but that is only a SMALL part of the story we PD's have experienced...you have explained relatively simple machining techniques that people like Eddy or myself can understand & produced the :gift results for our own eyes - however I still see years & years of experience behind the concepts & notes {& Bandits mathematics} :music
So the only two questions I ask .......
1) after the timing has been set & established...do you provide further match marking... then :crash the engine down to pieces.... spray with Loctite 7471 primer & the reassemble with a Loctite stud lock material?
2) you have used M4 & M :?: tappings & used stainless steel socket head cap screws... are you going to nominate a torque setting for the respective fastners :?:
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Hi Derek,
Glad you have enjoyed the build as much as I have, as you know I have a bit of a problem and doing this has forced me over the last couple of months or so to remain active both physically and mentally, so the build hasn't just been for the people that have been following it but for myself as well. That is why I take on projects that last a couple of months, I know that I can get that far before I have to put on my slippers and watch soaps on the box for a few days.
Now for your two questions.
With reference to marking, stripping down and rebuilding. This engine has to be stripped because there are a few things that need to be done, like the flats on the packing glands for the piston valves, but I won't do any more marking, just keep each end of the engine separate. On rebuild, I always use Hylomar jointing compound for all sealed joints, this acts like a mild threadlock for the holding bolts and screws. For the bits that might be forced to unscrew, the pivot pins on the joints for the eccentric to piston valve spool and the crosshead to conrod joint will get a drop of nutlock on the threads. By using stainless fasteners, not just for corrosion resistance, but also they have a bit of a 'grab' factor when tightened, so with the low vibration levels on this engine I don't expect to have anything come loose.
That brings me onto the second question about torque loading. Normally for larger sized bolts, a big shifter and white knuckles would do it, but for these small bolts, I don't think it is required and it would just complicate things. In fact I am having a bit of trouble with this area myself. I am trying to convert to being left handed and I just haven't got the 'feel' yet and am occasionally stripping out the hexagon heads of the screws so maybe I should get a small screwdriver torque wrench.
There is one thing I forgot about and that is the packing of steam glands. What I do is unwrap the 'string' into smaller threads, wrap it around the shaft I want to seal, then push it into gland with a thin piece of rod ( the one on piston valve is a bit tight but can be done), tighten up the nut until you have a gap of about 1mm between the nut and the gland and you can feel the friction being applied to the shaft, if too much friction just undo about 1/4 turn, if it can tighten all the way up, you need to put some more packing in.
I would like to add it is not just yourselves that have learned new things on this post. I have found out how to use my camera a lot more efficiently, plus all the related bits that go with it, like using the computer for graphics manipulation and video. How helpful people on this site are and their willingness to share information, not just with me but with everyone.
One disappointment is the feedback, I was expecting loads of questions, but very little materialized. Either I have explained well enough so questions were not needed, or it was totally above their heads and were afraid to ask because it might make them look silly. As I have said before, there is no such thing as a silly question, just a silly sod for not asking.
There have been a fair few hits on this posting, and looking by the number of times the pictures have been viewed there must be about 50 contemplating building, which is well above my wildest dreams, I was expecting four or five with an interest. Another way to look at is that next year the country will be flooded with far eastern made piston valve steam engines.
Now I have to find something else to make, this one is a none starter for horizontal conversion, it is just too long. Any suggestions will gratefully accepted, and I do mean that.
I want to do a final vid just to show how well the control valve works, but I want to do it outside in a different setting, but every time I try to set it up it starts raining. Maybe later today.
Thanks all, and keep the questions coming.
John & Bandit the Brain
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:D :D :D
Hi PD's,
I think we all owe John a huge amount of gratitude for this series of posts.
What a magnificent effort.
:great :no1 :respect
It just shows what can be achieved with very small budget and a bit of lateral thinking.
John's design should be easily achievable by others, even with only small/modest machines available. All this really means is that some elements of machining would take a little longer (lighter cuts), or perhaps require a slightly different method of work holding to suit the available equipment.
If I may, I would like to add a few notes regarding timing...... It Sure beats building kitchen units.... :oops :shhh
The biggest problem in all timing is finding the TRUE DEAD CENTRES.
On the surface, this may appear simple, but one thing, in particular, should be taken in to account..... Namely, LOST MOTION, and it's effect on angular rotation.
When the piston is being driven down by steam pressure the crosshead is being pushed, and hence the thrust is applied to the crankshaft side of the crosshead small end pin/bearing.
Conversely, when the piston is being driven in an upwards direction, by steam pressure from below, then the crosshead is being PULLED, as a result the thrust is now taken by the opposite side of the crosshead pin/bearing.
The same applies to the big end/crankpin/ bearing.
Whilst this may only amount to a small dimension (especially in a new engine, and assuming careful machining), it is, however, inevitable in any running bearing, and it creates the LOST MOTION I refer to.
Every time the piston changes direction, some piston motion is used up taking up the slack in the bearings (albeit a very small amount) without any actual motion of the crosshead and/or crankshaft. This is LOST MOTION.
It can, especially where large running clearances are involved (or in a worn/well used engine), make quite a large difference in angular position of the crankshaft when locating the TRUE DEAD CENTRES.
I attach a drawing and some text explaining how to find the true dead centres, taking into account any lost motion.
Once marked up, then it is easy to find the true dead centre positions for the crankshaft rotation.
It is well worth performing this task prior to attempting to set the eccentric angles and valve timing.
Incidentally, there will also be some LOST motion in the eccentric/eccentric strap bearing surface and the pin/bearing at the connection with the spool valve...... this must be minimised by close running tolerances, and allowed for in the valve setting.
One final point..... when setting the position of the valve spools (at TDC) it should be just about to open..... any actual open amount will reflect as a non-open amount when the piston is at BDC.... think about it..... which means the crank will need to pass BDC before the lower port opens.
For this reason alone, it is important to get the length between the spool lands dead right...... i.e. the same as the distance between the outer edges of the steam ports.
Ok PD's, That's my small contribution..... so AGAIN, very well done John and thanks on behalf of all PD's. :bravo :great :terrific :respect :respect2
So whats next?..... a true scale Titanic engine perhaps?..... Although this will mean the CAT will have to go to college and get a degree in maths as well...... you don't want to see the valve gear calculations involved.... :hehe :hehe
Best regards to all.
Sandy. :computer :beer :vacat
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Yes thanks John, I look forward to each Instalment
Peter
Ps. for those who like this sort of thing I have been following another build over the last few years
http://mokei-jouki.hp.infoseek.co.jp/e-Wiltop.htm
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John
I have followed your build with great interest,having not used a lathe
since I left High school,55 years ago. I found your packing instructions the
same as I would use to pack or repack steam rods on a pump or valves, lots
of graphite to lubricate them. Great site.
Regards Alex
From: "bogstandard" <livesteam@paddleducks.co.uk>
Reply-To: livesteam@paddleducks.co.uk
To: livesteam@paddleducks.co.uk
Subject: Re: Making a piston valve engine from mainly junk materials
Date: Tue, 17 Jul 2007 12:52:18 +0100
Hi Derek,
Glad you have enjoyed the build as much as I have, as you know I have a bit
of a problem and doing this has forced me over the last couple of months or
so to remain active both physically and mentally, so the build hasn't just
been for the people that have been following it but for myself as well.
That is why I take on projects that last a couple of months, I know that I
can get that far before I have to put on my slippers and watch soaps on the
box for a few days.
Now for your two questions.
With reference to marking, stripping down and rebuilding. This engine has
to be stripped because there are a few things that need to be done, like
the flats on the packing glands for the piston valves, but I won't do any
more marking, just keep each end of the engine separate. On rebuild, I
always use Hylomar jointing compound for all sealed joints, this acts like
a mild threadlock for the holding bolts and screws. For the bits that might
be forced to unscrew, the pivot pins on the joints for the eccentric to
piston valve spool and the crosshead to conrod joint will get a drop of
nutlock on the threads. By using stainless fasteners, not just for
corrosion resistance, but also they have a bit of a 'grab' factor when
tightened, so with the low vibration levels on this engine I don't expect
to have anything come loose.
That brings me onto the second question about torque loading. Normally for
larger sized bolts, a big shifter and white knuckles would do it, but for
these small bolts, I don't think it is required and it would just
complicate things. In fact I am having a bit of trouble with this area
myself. I am trying to convert to being left handed and I just haven't got
the 'feel' yet and am occasionally stripping out the hexagon heads of the
screws so maybe I should get a small screwdriver torque wrench.
There is one thing I forgot about and that is the packing of steam glands.
What I do is unwrap the 'string' into smaller threads, wrap it around the
shaft I want to seal, then push it into gland with a thin piece of rod (
the one on piston valve is a bit tight but can be done), tighten up the nut
until you have a gap of about 1mm between the nut and the gland and you can
feel the friction being applied to the shaft, if too much friction just
undo about 1/4 turn, if it can tighten all the way up, you need to put some
more packing in.
I would like to add it is not just yourselves that have learned new things
on this post. I have found out how to use my camera a lot more efficiently,
plus all the related bits that go with it, like using the computer for
graphics manipulation and video. How helpful people on this site are and
their willingness to share information, not just with me but with everyone.
One disappointment is the feedback, I was expecting loads of questions, but
very little materialized. Either I have explained well enough so questions
were not needed, or it was totally above their heads and were afraid to ask
because it might make them look silly. As I have said before, there is no
such thing as a silly question, just a silly sod for not asking.
There have been a fair few hits on this posting, and looking by the number
of times the pictures have been viewed there must be about 50 contemplating
building, which is well above my wildest dreams, I was expecting four or
five with an interest. Another way to look at is that next year the country
will be flooded with far eastern made piston valve steam engines.
Now I have to find something else to make, this one is a none starter for
horizontal conversion, it is just too long. Any suggestions will gratefully
accepted, and I do mean that.
I want to do a final vid just to show how well the control valve works, but
I want to do it outside in a different setting, but every time I try to set
it up it starts raining. Maybe later today.
Thanks all, and keep the questions coming.
John & Bandit the Brain
------------------------
Ever stop to think, and forget to start again?
Post generated using Mail2Forum
-
Sandy,
Many thanks for the compliment and the help you have given in the areas I didn't understand or fully able to explain, but as I said before I get enjoyment from this, and that is all the thanks that are needed.
Alex,
Start turning again, it keeps you going.
Peter,
I followed this fellows great efforts, well beyond my scope of doing things.
I look for shorter term projects.
John
-
I have to agree with everyone elses comments - An absolutely superb series of posts by John which just goes to show that even idiots like me have the ability to make their own steam angine with the guidance given in this series.
I think the reason for the lack of comments is twofold, firstly everything has been explained extremely well, and secondly, a lot of questions would probably only come about when you actually started to make the unit. It's one thing reading a series like this, it's another thing entirely to take it as the basis of making your own engine - Only then would a lot of questions really start to become apparent.
I still hope to have a go at something like this, but having just parted with almost £5000 for a car, it may be while before I can afford to start building up the required machinery etc. Though as a secondary point, it is good to know that you don't need to spend anywhere near as much as I had first thought! You need to buy good quality yes, but you can get away with not having some machines by using some of Johns techniques and a bit of lateral thinking.
Once again, my sincere thanks to John and to everyone else that contributed to such an unusual and well presented thread.
-
,
Peter,
I followed this fellows great efforts, well beyond my scope of doing things.
I look for shorter term projects.
John
John
I don't think you would have any problems matching his work. And on your bender you said you "may" need a rotary table to build it ,any other way to do it ? and how do I get a set of the plans of you OR can you post a fer more pictures of it , Or even a nice new next build .
thanks again Peter
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Hi Peter,
Because the plans are from a magazine article I don't want to infringe any copyright laws by doing a build on here as the build is already in the article.
The reason for the rotary table is to cut the grooves in the rollers using standard milling cutters, otherwise you have to grind lathe tools to a perfect semi circle of the correct size.
I don't want to turn this site into a model engineering one and I am sure everyone else doesn't, just want to show how basic model engineering can help people to achieve what they want in the pursuit of making model paddlers, and maybe offer advice on how to do it.
There are a lot of other sites dedicated to model engineering and I subscribe to a couple of those, but they are 'look what I have done' type sites, and don't seem to be geared towards the support of the kind I have received here.
John
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Here at last is my final video.
http://www.youtube.com/watch?v=gTuET23TkaI
I said before that the control valve was not as good as I expected. I have now changed my mind on that one. Being outside without all the compressor noise in the background I was able to hear the speed changes on the engine rather than having to rely on visual changes, and it does now come up to my ideal for a fairly easily made control valve, with no leakage.
John
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Ok John what are you Building Now ?? and how about some pictures . I miss getting up to what happened last night on the engine ,In fact I started staying up for the next instalment.
Peter
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Please remove
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Hi Peter,
Just taking a bit of a rest for the braincells and building a little engine from a set of plans.
Don't want to go into a lot of detail because it will be going off topic.
I think I started it last thursday and hope to have it running either today or tomorrow. Its called an elbow engine, six pistons but only five moving parts. Purely decorative, but was designed to show I think what is called a Hobsons coupling.
Here are a couple of pics of the build.
The flywheel came from a lump of 1" thick ali plate.
John
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Hi PD's.....our bogstandard said.......the flywheel came from a lump of 1" thick ali plate......oh yeh :?: :?: :?:
But :nono , our resident mathematician :mrgreen: Bandit tells me a different story John..... :rant .... that you pinched your wife's best heavy duty aluminium baking tray :music ...:shhh but :oops what will happen on Sunday when she goes to cook the roast dinner :lol:
-
Ha!, thats where you're wrong :nah
The better half doesn't cook sunday dinner. I know when my meals are ready when I hear a 'ding'
But just wait 'til she comes to turn the washing machine on.
I'm gonna cut Bandits tail off for snitching on me.
I've just caught him beating up the cat, so I whipped it off before he knew about it :twisted:
John with an axe
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Hello All,
Bet you lot thought I'd run away with the lodger, chance would be a fine thing.
I haven't forgotten about you, still call in about a hundred times a day, but very few posts recently.
I said at the end of my engine build that I was preparing for displaying my engines at the Malpas Yesteryear steam rally on Sept 8th & 9th, they are going onto the stand for the model boat club I belong to,
http://creweanddistrictmodelboatclub.org.uk/index.html
That was two plugs, and nobody noticed.
Anyway I thought I would show you a couple of engines I have knocked up in the last couple of weeks for displaying at the show ( still want a few more so will have to get my thinking cap on), in fact the small one I started yesterday, and got it running this afternoon. Don't tell the wife I'm a quick worker, she'll have me decorating in two shakes of a paintbrush.
Here's the first
http://www.youtube.com/watch?v=5ZRKNlY7enM
and the second
http://www.youtube.com/watch?v=76_TtDfYPCo
The second one actually uses a 1 Euro coin for the base, so it has cost me a lot of money to make, maybe 2 Euros.
After all this lot is over, I will be back with a vengeance, MAYBE (still in my mind yet) with something a bit special for all you steam paddler buffs.
John
-
Thanks John,
I still don't understand how the elbow engine works, and when you say tiny, you mean TINY!! :respect2
We go through periods when posts drop off - But I have to admit I was wondering if everyone had become monks and had taken a vow of silence!
Your just teasing us with the potential of a paddler engine! ;) Seriously, I cannot wait if it's anything like as good as your last project on Paddleducks!
-
Hi Eddy,
I've been bashing my two brain cells together for a few weeks now for a very slow revving horizontal engine, to save having a lot of big gears or pulleys to reduce the speed, but until I get the show over with I can't really get into it too deep. But if it does materialize it will be nowhere near as long as the last post because a lot of stuff was covered in that post and doesn't need to be repeated.
I need to get a bit more information about how sternwheelers work as I want to try and make two separate piston blocks so that they could be used in a normal paddler, close together, or in a sternwheeler with the cylinders extended to the outside of the boat and joined with just pipes and a coupling rod between them. Thats as far as I have got other than it will be a very long stroke engine.
John
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John
Here are some shots of the engine room of the Steam Tug Portland. She was the last working steam sternwheeler in Portland Oregon USA is now a musium and can still be steamed. Engines developed 900 hp 26" bore 9 foot stroke.
Dave
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More shots
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Hi Lads,
What size lathe do you think I've got, no way am I going to make a 12" scale version, that would take at least a fortnight of my time. Thanks for the photos anyway, very interesting.
What I was really after is how they do the basic drive installations on MODEL sternwheelers.
Thanks again
John
-
John
In 1/32nd scale that makes an engine with bore of .812" and stroke of 3.375" the hull will be a little over 6' long and 20" wide.
Dave
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Thanks Dave,
I wasn't far out in my head calculations, I was looking at 3/8" bore by 1.5" stroke (4 to 1 ratio), which is about half of your calculations. But does give a bit of a funny scale for a sternwheeler but it would be a manageable size.
Many thanks
John
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I know you like "different" engines Have you seen the Halo. Peter
http://lineymachine.googlepages.com/
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Hi Peter,
I contacted him about two months ago to see when he is releasing the plans for the Halo. He told me early August, so I am waiting for it to appear on his web site.
John
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He has got the Kits for sale now ..But you have a BIG scrap bin...Peter
http://cgi.ebay.com/Pushrod-Operated-Radial-Air-Steam-Engine-MACHINIST-KIT_W0QQitemZ110156769244QQihZ001QQcategoryZ2594QQtcZphotoQQcmdZViewItem
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Hi Peter,
Looks fairly easy to make, just repetitive parts making, five of most things, ten of a few others, plus a few one offs. I should think somewhere around a month should see it done.
I will wait for him to get all his notes sorted first, then maybe he will have a few mods to be done.
I am just designing a twin cylinder flame gulper for this show I am attending, so I have that to build next week.
And that brings me to this weeks little project.
You must remember by now that I built one of these steam engines in parallel to the prototype. Well I have finished doing all the custom parts, and now on the pic you can get an idea of what I will be doing.
To keep Derek happy I have taper turned the columns, plus you will notice the lovely pink background, I know that he is going thru a Barbie phase so I thought it would cheer him up.
The cylinder block has been machined to simulate separate cylinders and the relief that is machined in the side has been painted in Ford Modeena Green, which I think is the perfect complimentary colour for this engine, besides the fact it was the only gloss spray can I had in my workshop.
The engine turning took over five hours to do to get the holographic effect I was after.
The next post will be the custom engine assembled.
John
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Hi PD's.... :hmph nice how a 5/8" diameter five start straight fluted UNEF plug tap can be converted :hammer into a lubricator looking device.... & the brass plating is a superb job
It must have near the equivalent surface area as SCOTLAND.... :ohno you may end up FREEZING the steam...........& the tapered columns look well proportioned :crash in taper :music
Oh BTW John....we don't have Barbies in OZ... we have pet Witichie "D" Grubs :hehe
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Hi Derek,
Don't usually hear from you until tomorrow morning (GMT), are you throwing a sickie and staying off work for the day?
Got a bit carried away with the luber, didn't quite look right with just straight fins, so I thought machine a bit away, ended up with about 90 separate fins.
The taper on the columns is about 4deg inclusive, the prob was I don't have a taper turning attachment and I didn't fancy kicking the tailstock over, so used the topslide on the compound. Not enough reach on that so had to make something up for the top. It doesn't look too bad when assembled.
By the way don't understand this -
Oh BTW John....we don't have Barbies in OZ... we have pet Witichie "D" Grubs
Please explain in words of two syllables or less so that I can understand.
John
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John,
The engines I have started designing for my stern wheeler in 1/2" = 1' have a bore of 1/2" by 2 1/4" stroke. Will have a hull length of 68" x 13' beam.
check our (Paddleducks) downloads section and check E. T. Westbury's stern wheeler engine.
Bill
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Hi Bill,
Thanks for the input, I had already looked at this set of plans.
They are really designed for a fairly experienced machinist in mind and I was looking to make an engine that is semi universal which with slight modification could be used with both sidewheelers and sternwheelers and still look fairly authentic, and to power a model sternwheeler of about 4ft or a sidewheeler a little larger.
The main criteria being that it can be made by someone with a fairly basic machining setup and with a little help by being 'talked' thru it, be able to produce a working, useable engine.
This time though, I am considering building one first just to prove the design, rather than this build which materialized as it went along, which was a bit of a strain on the old braincells at times.
Thanks again
John
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OK PD's .....& a few corrections :sorry
a) no John - self employed persons are not allowed :nono to take sickies
b) @ 0600 AEST this morning I could not resist commenting :clap on the oiler
c) when I termed the lubricator as a converted 5/8" diameter five start single fluted UNEF tap.... :music .. I was totally incorrect as you have explained the 90 cutting landings....so :thinking :shoot and after recalculating this it must be
a 5/8" five start straight fluted LEFT handed BSF tap ....as clearly you wouldn't need or purchase any of that 60 degree YANK reject stuff :news :post :great :oops
d) in OZ we do have BARBIES.... but these are when a few mates get a small fire + a hotplate going + some prawns + garlic + a few shelias + a few :beer ... so what happens :?: - the girls cook the prawns & the Witichie "D" Grubs on the barbie & we have the :beer
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That's better, back on GMT, the civilised time.
:lol:
Aha! Self employed - overpaid, underworked and pays no tax, I always thought of becoming one of those. Maybe I will have a go sometime. :sunglasses
Misunderstanding of cultures going on here, the 'Barbie' I mentioned is a small girlie doll, usually attired in pink or shades of. :ohno
Nearly there on the tap size but this is a custom job, 5/8", straight six flute with a square section thread, but this is where the custom bit comes in, it can cut either left or right hand, just depends which way you turn it, flexible cutting teeth and all that. :nah
Anyway all this idle gossip isn't getting anything done, I've got an engine to assemble today.
John
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John, Westbury's engine does seem a bit complicated for a beginner and it is not really traditional in design but I'm sure it works fine. I think If I were to design around that engine for a first timer I would go with piston valves.
I am designing my engines around the engines found in the booklet The Marine Iron Works Of Chicago U.S.A. The source of that booklet is mentioned in the "paddle wheels" forum of PD under the thread of "pitmans revisited."
Bill
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Bill,
It will have piston valves, as the one on this build. It was Sandy from ACS who explained it all to me and now I have the grasp of it, the system seems ideal for these easy to make and easy to control engines, no difficult reversing systems.
But I have such a lot to do at the moment I just won't be able to get round to it for a couple of months at least. This one is sixth in the project queue at the moment, and that's if I don't get another commission.
John
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Hi All,
Hopefully this is the final part in the build saga of this engine.
As you know, I built two in parallel, and the second one I decided to give it a bit of a 'lift' from the basic design and hopefully if anyone ever decides to make this engine, it will give them a few ideas to make it different.
The first four are different views of the engine and the last is showing the two together.
John
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Goodness PD's ....over the past months I have posted a few humble :bow re the build/s by our John [bogstandard] work...& tonight we see the culmination of the past work between the No 1 & No 2 engine
so from here :thinking I will offer comments from 20,000 Km away
a) 10 out of 10 for the new base mounting rails
b) 10 out of 10 for the new flywheel drillings
c) 20 out of 10 for the new square to round tapered engine columns.......
d) 10 out of 10 for the engine block seperated & painted GREEN
e) 2 out of 10 for your steam discharge tube exiting the reversing valve....the bend on the 180 degree line is out of wack!!!!!!!!!
f) your 90 tooooooooootht cooled lubricator......I would prefer not to comment on :hehe
John.......I know I speak on behalf of all PD's :respect & thank you for the series of both the osilitator & the P/S valve engines ......made from JUNK
....& we look forward to the next set of installments HORIZONTAL - ..............................................your colleague [& @ 57 YO still a student ] in OZ :angel :beer regards
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I want to know how he milled the centre out of the block and made it round on the inside ??
Peter
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Well John, that is just too pretty for words.
Bill
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Peter,
You must know that cats have very rough tongues.
Well I coated where I wanted the metal removed with double cream and gave it to the cat to lick on.
Back in the real world, I mounted each cylinder bore in turn on a mandrel mounted on my rotary table, and machined away an arc using the same centreline as the bore, taking care I didn't break into the mounting holes coming from underneath the block.
Derek,
Thanks for the compliments.
'nuff said :nah
Bill,
I did this to show that a totally ugly engine like this one in the prototype form can be made to look almost nice with just a little work.
John
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OK..... :hehe & just :thinking PD's....but could the engine builder please explain the question in the attachment :mrgreen: :kewl
:sorry ...the text is so small....the question is..."how did you tighten this SHCS [socket head cap screw] ....an answer of a...'bald headed :oops: woman or a ball headed allen key is not acceptable' :nono
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With a long series ball ended allen key
It is a bit of an optical effect but the flange on the u-tube is offset to allow the u- tube to miss the pipe below it. If I hadn't have done that way, it would have meant a very complicated silver soldering and port drilling exercise to keep the pressure and exhaust separate, which would have entailed using a 5/8" dia., six fluted, 90 tooth, square section, unique left/right cutting, brass plated plug tap, which I have misplaced somewhere, so I had to take the easy way out and offset the flange.
John
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deleted................. Derek
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I would have made some comment, but the technical jargon is beyond me. If there are no electrons, then its not for me. I will just say that it is a superb piece of work, and I am envious that I do not have those talents. Well done.
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How about that, 14 pages. Too bad this could not be editeded down some and poted on our filea secton in zip so it could be down lowded easily.
Hank
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Oldie,
Everyone has a talent, but wouldn't life be boring if we all did the same thing, I am sure that you have a talent that I am envious of.
Hi Hank,
Have a word with Eddie, he might be able to do it.
I have all the pics and sketches plus vids but not the text, if that is any use to you.
John
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For what it's worth, I have taken the liberty of combining most of John's text (and some of the comments) into a single document (MS Word). I'm in the process of inserting the pictures/sketches as appropriate but reducing them in size, which may limit their usefulness for someone using the document as a 'how-to' manual.
Solution may be to produce the package in two parts: (1) the text (with small pictures); and (2) a separate compilation of the pictures/sketches in full size, cross-referenced accordingly. However, file size may be an issue - I'm only half-way through page 3 of John's postings and already the file is close to 4 megs :cry:
Will work on it and see what develops. Be warned, however, that John can doubtless produce a steam engine quicker than I can replicate his instructions on how to do it! :oops:
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John this chap is Almost as quick as you but your flywheels are round and not nearly round like these.
Peter
http://www.grahamind.com/movies.html
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Bit too slow for me Peter, but I suppose it could be speeded up a little with a bit more programming.
But it does go to show that engineering in that sense is a fast disappearing art form, soon most stuff will be made by programmers rather than artisan machinists.
John
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It looks to me like he does not have his stook positioned acuratly for the flywheel, if I was running it I would change the tool radius setting for that final two passes on the outside of the wheel which would give you a slightly smaller wheel, but one which is fully machined.
Regards,
Gerald
PS the Programmer can be just as artistic as an artisan machinists
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Hi Steamboat,
There was never any reference to programmers being non artistic, in fact they have the capabilities to produce items in minutes that would take weeks by hand machining, and to a more finite degree to artistic licence if so required.
What I was inferring is that manual engineering is on a downward spiral decline, in fact two machine shops in my area have closed in the last six months.
Going are the days when you could stroll down to a workshop and ask them to knock a few thou off this, or weld it up and machine it back to size.
It is for this reason I receive many calls a month asking for me to do 'just jobs' in my home workshop, and I try to accommodate as much as possible but I personally cannot hope to cover all the jobs that require doing.
Large workshops cannot get enough work to keep everyone employed and small one man bands like myself who do it as a hobby can't keep up with demand. Where do we go from here?
John
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John
I've just got some stepper motors and some spare lead screws or whatever they call them on mills . I've been wanting to do this this for a number of years. its not that I think it will turn me in to a great engineer its just so I can get all the openings for windows about the sameish size in wood plastic or brass. I've just spent 3 days making ally window frames for a boat five in all just thin ally hoops , it is taking longer to polish them another 4 days up to now and my hands are like ballons so ill have a break John when is your show you have been building for and what is the acess like.Peter
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Hi Peter,
I know exactly how you feel about the cutting and polishing, but I enjoy doing it all by hand, and the feeling when it is all done and dusted is great. Gives me a grin for days with the feeling of a job well done.
The show at Malpas is on the 8th & 9th of September. If it is wheelchair access you are on about I wouldn't recommend it as it is set in a small sort of valley with grass slopes everywhere, but you cannot blame the organizers because it is a large show and they have to take what they can get, not many farmers want their ploughing done at that time of year.
John
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the text is so small....the question is..."how did you tighten this SHCS [socket head cap screw] ....an answer of a...'bald headed :oops: woman or a ball headed allen key is not acceptable' :nono
I have a nice set of Hex drivers. Basically a screwdriver with an allen key head. They are available from almost any hobby store.
I race RC Cars and they are an absolute necessity.
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Hi PD's ....& as our John.......... [bogstandard] says....
Large workshops cannot get enough work to keep everyone employed and small one man bands like myself who do it as a hobby can't keep up with demand. Where do we go from here?
...it is the same here in OZ, the best apprentices end up in air conditioned offices punching numbers into the MAZAK :computer & are rewarded by increased $ in their pay packet [which is now an electronic transfer of funds]
It is the old supply & demand function......however there are fewer younger replacement compentent trades engineering machinists to take up the shortfall
Successive Governments world wide have recently produced [twenty years] of University qualified engineers who I am sure are mathmatically brillant, but who were not trained to set the tool post tool height at 0.002" lower the axis of the work :crash .....I am sure you will understand what I mean :darn :ohno
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Hi Derek,
I have been saying this about de-skilling ever since they did away with apprenticeships years ago in favour of university places.
There is no one to take the place of the skilled craftsmen when they retire or snuff it.
John
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Have just finished producing a first draft transcript of John's engine build description. However, it's ended up being 84 pages and almost 17 megs in PDF format. (The zipped MS Doc file is over 23 megs - the pictures don't compress very much!)
NOW I've discovered the size limit for attachments. Is there any alternative to the 4 meg limit on attachments to a post? If not, will break the document into chapters - not as tidy, but will work.
Floyd
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The 4Mb upload limit is set by our host Floyd, so sadly we're stuck with it :(
You could send the file to me and I can place it in our Downloads section, but it would break my email inbox size, so you would have to send it via snailmail....
Other than that, the only alternative is to break it into 4Mb chunks.
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I've caused a lot of trouble here haven't I.
I should have been a bit more concise in the instructions rather than rambling on.
John
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Well PD's.......what do we say :?:
1) has BogStandard wofffeled TOO much :roll:
2) has our PD Membership benifited from the 'bit a junk'''''' postings :?:
I am but a/an humble :towel member from OZ, but I know where my VOTE is...... :yeah toward Mr BogStandard......
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Without the input from the" brains" in the team and all the extra advice It would have been very hard for a thick person like me to folow.Peter
(Picture of the brains of the posts)
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Not to worry, John. For a rank amateur like myself (only the simplest of Stuart's kits under my belt), learned more from your posts on tips for using a lathe than any other source I've come across! Still amazed at not only your machining ability (not to mention photography) but your generosity in sharing that skill with the rest of us - much appreciated by many, I'm sure! :terrific
As for the transcript, will see what I can do. Not an expert in dealing with the 'Net, but figure there's got to be a solution lurking somewhere - give me a few days!
If all else fails, I'll have a consolidated document for my own use when I tackle your engine!
Floyd
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This post seems to go on and on, but that will finish when I get your new engine underway.
Here is my final engine build for my show, took three days and very precise machining, again my own design, did it as I went along. The plexiglass is in fact bullet proof plastic, just to retain the bearing bits if they shatter. I haven't had my tacho on it yet but it will definitely exceed the 39,000 rpm which is the bearing limitation.
Don't try putting one of these in a paddler.
http://www.youtube.com/watch?v=wImhE-zNTgk
John
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Fantastic John, the sound of that turbine winding up is amazing!
So the gearbox will be next, and then a model of Turbinia? ;)
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Hi Eddy,
Have got a gearbox to fit to it but I am going to use it to generate electricity for effect.
John
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I'll get you to build a boat yet John! :) Preferably a paddler of course!!
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I've been building model boats for over 40 years, but the choice had to be made, engineering or boats, and because engineering is easier for my arm the boats have got to go, how many do you want?
John
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Well, if their free to a good home :angel
Being unemployed and our family holiday coming up in a few weeks time, I don't think my wife would be impressed if I went and bought a model right now! :(
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After a cursory investigation regarding uploading a large file, decided the simplest solution was to divide it into smaller parts. As a result, the record of John's design and build is now in six chapters plus a two-part appendix with sketches in full size. The original document is in MS Word but have generated PDF version for posting.
Here is the first chapter. (Assuming I've got the attachment procedure correct!)
If it works and there is no violent dissension, will upload remaining bits in due course.
Floyd
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oops: Got an error message on that attempt to attach Chapter 1!
Will let my computer cool off and try later :crash
Floyd
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Hi Floyd,
Absolutely fantastic job you have done there, a credit to your editing skills, it actually makes my posts look almost professional. I just wish I had talents like that.
I just dropped in today to put up a little post but when I saw this - WOW!! and WELL DONE.
Anyway, here is why I called in here in the first place, to show you what I get up to when I am not making these 'silly little engines', as some of my mates call them.
Today it is big boys toys, in the form of a rigid 'chopper' frame, it cost the chap one arm and two legs when he had it built a few years back, so I didn't really want the job just in case, but he is going to landscape my garden in payment (he hasn't seen it in daylight), so I reluctantly snatched his hand off. Modifying the back end to take chain drive instead of shaft drive, just a matter of a couple of slots, plus a few 'custom' stainless and aluminium bits.
Anyway rambled on about this enough, here is the piccy of the frame pushing the miller to its limits, only just enough room to get the cutter in. Plus the large grey thing in the background with the 'Charlie Chaplin' work trousers is yours truly (wear what the occasion calls for).
So if you see this person hanging about at a show come and introduce yourself.
John
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Hi John,
Glad you thought it was OK! Not much credit to me - you're the one that created the content! :respect2
Pleasantly surprised, though, when I came back on and saw that the attachment actually made it - notwithstanding the error message I got! Will proceed with the remaining chapters over the next little while.
Good to be able to put a face to the name! However, doubt that our paths will cross, given the wee bit of water that stands in the way.
Got a chuckle with the understated way you refer to the modifications to the chopper frame as only "a matter of a couple of slots, plus a few 'custom' stainless and aluminium bits", although for you, that might just be the case!
Here goes for another chapter. Cheers,
Floyd
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Keeping it simple now! Here's Chapter 3.
Floyd
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Keeping it simple now! Here's Chapter 3.
Floyd
How about posting these as a separate topic with a directive her to it. It would be much easier to access. Just a thought.
Bill
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Good thought! Makes sense! However, new to all these 'Forum' machinations and just hanging on by my fingernails :ohno
Figured someone (you know - the mythical 'They') would gather up the pieces and put them in some type of repository to facilitate access.
If that's not the case, will create separate topic as you suggest. (Assume the chapters already posted here would have to be reposted under the new topic to make a complete package?)
Will wait a bit for any other feedback, then proceed with Plan B.
Floyd
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Just keep posting as normal Floyd and I'll sort it when we have all the parts...
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Roger that! Here's Chapter 4.
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Moving right along - although not as quick as John!
Here's Chapter 5.
Floyd
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Hi Floyd,
You're doing a great job here, I am sure that a few other people appreciate it as well.
I'm glad you got a 'chuckle' out of my comment, but I have to admit, I didn't do this job alone, I can only lift with one hand so I collared my mate in to help me, he was the one taking the pics. He is as far as I am concerned a 'great' machinist, if it can be drawn he will most probably be able to make it manually, he makes me look like a rank amateur, and is my mentor and instructor all in one, and has been for the last 20 odd years.
Put it this way, if you have flown, and the aircraft had R-R engines he was most probably responsible for the overseeing of the machining of all the compressor vanes in there.
John
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Hi John,
As I mentioned at the start, I was doing this for my own use so really only needed to be 'tidied up' for wider dissemination. Will be interesting to see if anyone takes a shot at building one.
BTW - I've got my pile of 'junk' assembled but suspect I'll first tackle the casting kit (PM Research) I've got on hand before I take on a full scratch build!
Here's the last Chapter; next the appendix with your sketches and we're done!
Now if I could just come up with a pithy saying for my signature block! :thinking
Floyd
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Hey folks - that went well - no error message and the post w/attachment was right there!
On a roll - here's Part A to the appendix before the gremlins find out they missed.
Floyd
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And here's the last part.
A note for readers: the PDF files are formatted to display a page size of 81/2 x 11 inches, which is of little consequence when viewing on a computer screen. However, if readers wish to print off a hard copy, they are reminded to change their paper size if necessary, eg, A4 in Europe.
Again, my hat off to John for all the time and effort he put in to describing this build. I'll keep an eye out on YouTube for more of his creations - keep up the great work, Bogstandard!
Floyd
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Knew it was be too good to last!
For info, here's the type of error message I kept getting for 6 of the 8 posts:
Fatal error: Allowed memory size of 20971520 bytes exhausted (tried to allocate 4880844 bytes) in /home/fhlinux208/p/paddleducks.co.uk/user/htdocs/forum/m2f/includes/pear/Mail/mimePart.php on line 236
Fortunately, though, 'Fatal' didn't turn out to be quite correct, as the attachment eventually did appear after an indeterminate time!
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Floyd,
Very well done, and a big THANK YOU.
Nothing new for the time being on the new engine side, maybe in a couple of weeks after my 'display' is over.
John
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I've edited Johns first post on making the steam engine, so it now includes a link to all the pdf files created by Floyd. Our sincere thanks to everyone involved for creating such an interesting and invaluable piece of work!
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John & Floyd, Great joint effort. Finished up by Eddie with posting to the download section under steam engines gives it all a final touch. Thanks Eddie.
Bill
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Well John (Bogstandard) how did the show go at the week end, any Pictures.?
Peter
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Hi Peter,
It was a steam fair, so the only pics I took were of stationary engines and a few 3 & 4" scale traction engines. I had a ten minute walk around each day and took a few piccies.
All the other time of the seven hours each day was spent explaining how my engines work on the most visited stand in the modelling tent, they were two deep most of the time, especially when I run up my air turbine generator. Just wait until next year when I get a bit more organised and maybe someone trained up to give me a break. This is what brought them to the stand.
http://www.youtube.com/watch?v=KW6V7JWbQwk
I found a dozen people who were really interested in building my piston valve engine, and so I gave them a disc each with all the plans on, on the understanding that they show me their results.
John
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Just for a bit of interest about the engines I make, here is one I got running yesterday. It is still in rough form and needs a bit more brightware detailing to get it looking right. But where this one scores is that I took a single cylinder design and added another cylinder to make a boxer configuration and made the burners fixed at the 'sweet' spot. These flame gulper engines are only supposed to be run in a draught free environment and not moved while running because any excuse and they will stop. This one will even run outside because of the fixed burners. When I contacted the original designer, Jan Ridders in the Netherlands, he couldn't believe it, until he saw this video. So now he is going to build one like mine to prove it to himself.
Fame at last.
http://www.youtube.com/watch?v=IyrWRBoC-2c
John
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John and All:
Just a word to say thanks for your great effort on this engine and plans.
I'm on the look out now for materials and will start my build soon. I've almost completed a 3d model of the engine and will see if I can perhaps modify some of the shafts etc. to mach my imperial tooling.
Regards Doug (Canada)
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I've almost completed the 3d model, thus far it is per plans no changes to imperial yet.
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another shot
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Doug,
I made a 1.5x version of this engine using "imperial measures". I found that the sizes of the rods and fasteners made no difference. Likewise diameters of the pistons and valves. Any linear dimensions I just multiplied by a consistent metric->imperial factor; since my mill has a DRO, any odd thousands measurement didn't pose a problem.
Kirk