Paddleducks
Other Marine Models => Live steam => Topic started by: R.G.Y. on November 01, 2009, 06:58:05 AM
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The trouble with paddlers is the stability. unfortunately boilers have a high center of gravity. Having studied MODEL BOILERS AND BOILER MAKING by K.N.HARRIS. I saw a sketch of a boiler invented by a Mr wedge, the wedge boiler a water tube boiler consists of 3 layers of tubes the middle layer set 90o to the others. Wide but low ideal for a paddler. Unfortunately no details so I have drawn up my own design and have done all the calculations. I have started con strution. That is the easy bit certification is the hard part. My model engineering club (toy train club) tester said he can,t test a none approved design, wouldn't even look at my calculations. To get approval will cost £400 by the Royal Alliance. R.G.Y.
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With the changes in boiler testing regulations, the smaller boilers often do not need to have a test certificate Geoff.... It's all down to their capacity and working pressure. Of course testing is always advisable.
Take a look at the following document in our Downloads area - I know very little about steam power, so it's as clear as mud to me, but hopefully it will make sense to you?
http://www.paddleducks.co.uk/smf/index.php?action=downloads;sa=view;down=304
Regards
Eddy
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Please don't accept ANY advice to ignore the need for proper cerification for boilers. My father suffered very badly from an exploded boiler, and even small vessels are a danger to health. Go through the red tape come what may.
You've met me, and know how I am fairly laid back...but not with pressure vessels of any type-it aint worth it.
Matt
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I never said it shouldn't be tested Matt - I simply said it doesn't require a test certificate! A totally different ballgame!
I'd certainly always advise that a boiler should be tested to ensure it's safe - But the certificate isn't required, that's the way the law currently stands as far as I'm aware.
Regards
Eddy
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Interesting project. If I understand your description correctly, the water tubes will be under the boiler, like the Yarrow type?
What exactly is an approved boiler design in the UK, who approves it?
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Interesting project. If I understand your description correctly, the water tubes will be under the boiler, like the Yarrow type?
What exactly is an approved boiler design in the UK, who approves it?
An approved insurance examiner who is usually involved on a local level with a model engineeering society either on a local or national level. This is normal for any club insurance to be maintained and there is a requirement within most clubs own safety policy to have the boiler re-certified at an agreed period. Most people would buy a commercially produced boiler in the first instance and that way get a manufacturers certificate at purchase.
cheers
Jim
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The issue is not simply testing, it is approval. There are too many people making unapproved boilers out of bits of copper pipe these days. My message is to stop playing about with your own safety and build ONLY from approved designs and ensure that your pressure vessels fit within the PSSR-even if they don't have to.
Serious injury could result without regards to this.
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The issue is not simply testing, it is approval. There are too many people making unapproved boilers out of bits of copper pipe these days. My message is to stop playing about with your own safety and build ONLY from approved designs and ensure that your pressure vessels fit within the PSSR-even if they don't have to.
Serious injury could result without regards to this.
Absolutely Matt, always use an approved design. Then as any responsible boating member will be a member of their local club, remember to keep your compliance up to date,
Jim
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Eddy I think you are partly correct under 3 bar litres they are exempt but i am sure your club tester would
say the same thing he could not test it.
it all boils down to, you can make it, test it, sell it as part of a package ie complete loco(not sure about a boat possibly a complete steam boat) but not insure it for public usage unless it has been tested by an approved body this is for under 3 bar litres
it seems the new laws have changed too much for boiler testers to say yes or no, they can approve them if
suitably qualified but I suspect nobody is prepared to do this now.
I work for a steam building company so I see boilers made and tested I believe testing above 3 bar litres is about £600 or so for an approved design.
another note ALL boilers should be properly pressure tested and correct steam test before use
holding the required pressure is only part, it must not look like a banana after testing so measurements taken
before and after are required.....
and I do make my own COPPER boilers and will continue to do so as a hobbyist they don't get approved or insured as I have my own track.....ask me in 20 years time if any of them have blew up though
Steven
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Nice to know the Monarck's captain remembers me. you will be pleased to hear I will not be useing any old tube. I will be pressure testing to twice the working pressure. As for 3 bar-liter rules I read it as no more tests after the first, not no test at all. Also I have been told a lot of the published (approved) designs are rubbish? Yes it is a water tube boiler (as yarrow) where the fire is out side the boiler & inside a caseing. I plan to line my mild steel case with 1/2" thermalight block (insulation building brick). Another advantage with this design small tubes less area =less pressure. A lot of interst thats good. R.G.Y
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Do you want some proper refractory, I don't know if it will cast well on a small scale, but I can post some out to you if you fancy?
Glad you're not mucking about with plumbing supplies though!! :P
And I always remember my punters! Although I may not be at Monarch's helm much longer, things are changing in life and next season may be my last :(
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Opps........second slip tonight ....had not looked @ the recent .......reference link from Eddy earlier tonight......
Hi PD's.....we do have 'a reference' to the 2007 British boiler Standards in our WEB pages courtesy of Sandy Campbell........ Derek
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RGY ,I would be interested to see it built,how about using ceramic fibre then it will give heat back into the boiler chamber but use thick stuff I tried some 2mm i had but its too thin, 6mm I think would be fine gives similar results
as ceramic plaque used in burner contruction ie it glows red....
Steven
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I've got tons of that too if anyone wants some!
Matt
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Thanks for the offer Matt. I think the block will be lighter, and easier use, but the joints made with fire cement.
The ceramic no better than the block, they also glow red and reflect the heat. I use them as a silver soldering hearth. Fixing to the case is no problem, it can take a double helix screw.
The model engineers societies boiler regs; up dated November 2008, I have seen a copy, put don't have access at the present. R.G.Y.
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The presant state of play, ready for the solder. Geoff.
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Now thats interesting Geoff,
I do like the idea,I've not seen one like that before, to me they look like 22mm pipes but i cannot convince myself
I would suspect more 28mm,are you going to use 2 stage soldering or all in one go.
good luck with the silver soldering,on my boilers, i am always a bit nervous until it passes the pressure test.
regards
Steven
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Where is the minimum water level going to be? At the bottom of the top pipe?
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28mm external diameter pipe. Two step soldering first step join pipes and fix safty valve bush, and bushes to end caps. Second step fit end caps. The reason is I will need to remove the ends of the 15mm pipes used to aline the holes in the 28mm pipes deuing assemble. Top pipe steam space. Below the drawings for the case. The calculations I am keeping till later as this is ansome what experimental. Geoff.
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Hi Geoff,
at present I cannot view the files as I am using a mac,but I will later,I would suspect you have the heat pass
twice around the pipes,bottom 2 then the middle 3 then out the chimney ,
somthing to think about in my gauge1 It is difficult to know how much water is in the boiler might be worth
making a hole in an endcap for a bush for an electonic water level gauge
Regards
Steven
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Steven, When you get to see the plan every thing will be clear. It must be OK viewed 15 times and no comments yet. Good or bad.Geoff.
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Hi Geoff,
just manage to view your files it looks good
I can see now how the gauges ect are fitted.
I see there has been quite some thought gone into this boiler.
you could use ceramic and angle toward the bottom tubes like a portable gas fire
one on each side.
but i am always saying this as l like ceramic plaque as it is very simple and very efficient .
Steven
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Steven , I am not sure about this ceramic stuff. Do you mean for insulation or the burners or both? I had planed on using tube burners and thermalight block for the insulation. ( the light blue dotted line on the drawing. Any advice gratefully received. Geoff
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Geoff ,
I use this stuff for gas work as it is the best I have seen
have to excuse the strange shape for the burner box but my father built the boiler and placed
the firebox too far under the rear axle hence the shape,but it works well.
ceramic plaque is for burners as it has holes in for gas mixture.
ceramic fibre is the insulation
at some point another photo tonight showing ceramic fiber
steven
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Steven, how big is the boiler in the photo? Have you not had time for more pictures?
I have done more work on my boiler and made an alteration to the plan. the photo shows the bushes and the safety valve. center forground is the improvement! the check valve on the end of square to be screwed into bush in boiler, the hole doesn't go strait through, the water will pass through a tube over the burner before going back in the other connection and into the boiler. An identical fitting will do the same for the steam out, but much nearer the heat. geoff a long wait for a reply had computer trouble.
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Hi Geoff,
I have been busy!,
ok boiler is 2"dia 7 1/4 long burner is about 1 * 1.5 "
added photo of under loco
you are using what I would say is a good technique by warming cold water before it reaches the boiler and drying the steam output
i have not had time to do photo but I will
what I wanted to show is how it reacts to the heat of a small propane torch
being thin it seems to get a bit brown but still glows red and I can hold it within my hand while being heated without getting burnt, only I have to watch for the
bits not covered by my hand as the propane torch has a wide flame!!!
oh and remember this is only 2mm thick!
Steven
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Steven, Nice one 23 veiws already so some interest but no comments so far. The ceramic insulation I am sure is very good. I will try the block as i need to fill the case close to the pipes. I will keep you posted on progress. and any one else who may be interested. geoff.
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Steven, Nice one 23 veiws already so some interest but no comments so far. The ceramic insulation I am sure is very good. I will try the block as i need to fill the case close to the pipes. I will keep you posted on progress. and any one else who may be interested. geoff.
Always interested Geoff and Steven. Although there are many views for teh subject of this thread it isn't always appropriate to leave a comment. I know that the level of engineering shown on here is astounding and i for one don't feel confident in replyiong to a subject that I know absolutely nothing about but do appreciate seeing other peoples ideas, work and progress.
Thanks for sharing these with us so far
cheers
Jim
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same here, it's always interesting to see how these things are done - even though I'm unlikely/unable to build one myself :D
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Yep have to agree it interests me to. Unfortunately I don't fully understand which is a real pity as i have a Roundhouse loco sitting in a box half built and i haven't a clue / to scared to do anything with it :(
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I've always been interested in steam,of any description,a pet interest is boilers,
I am in the middle of designing a vertical with a 54mm copper tube only cause I have some spare!.the thing that I have noticed is heat/flame path keep it a slow as
possible,in a vertical boiler heat goes straight up the flue if using a single central pipe with gas, well you heat the chimney more than the boiler,simply natural aspiration of a vertical and coupled with blast pipe equals a good draw from the fire,so a way to slow this down has to be found ,the same is true for any small boiler,other peoples test results with ceramic seem to indicate that heat drop after
about 3-4 (3/4 flue)inches in a horizontal boiler,the heating properties drop very quickly,
so in my design i use 3 off 22mm end stops coupled to 8 or 10mm flue tube coil wound about 5 close coupled coils(hard part) as small a diameter as I can do then goes to the central stay at the top of the boiler where they are joined so the only possible non part that cannot be soldered easy from the outside is the join from flue to 22mm end stop.
using 3 off 1/2 dia ceramic burners,the interesting point is to see if the design
will work...
this is just to give food for thought as in everything experimentation is needed
i am not a qualified engineer I am simply just a turner with, to me, a rewarding and interesting job,its even worse as i do it as a hobby!
Geoff as always I am interested in how you progress,
Regards
Steven
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Yes I am pleased over 500 read es. But I am no expert just a rough carpenter (retiered) with no engineering training, but I do visit the library and they always get the obscure books required. So thanks for the encouragement. Another advantage with this boiler is most of the complication concerns the case. The boiler it's self has no stays no internal tubes, and the fittings are available commercially, although I have made my own. The most difficult is the silver soldering and this is easier than soft soldering given enough heat. I believe the ability to use tools is the important requirement, and you can do that can't you Jim, Mike & Talisman. Thanks for the interest. Geoff
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. I believe the ability to use tools is the important requirement, and you can do that can't you Jim, Mike & Talisman. Thanks for the interest. Geoff
Reminds me off my induction training to the band saw by my dad when i was about 12 -
Now Son, i have a friend that lost 2 fingers using a bandsaw. He was cutting a piece of wood when his wife walked into the room - an attractive blond with no clothes on - his attention wandered from the saw to the wife while cutting - Remember son allways concentrate on the machine.
To this day i still have ten fingers and one eye on the door :hehe
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It reminds me of my grammar school days - Our woodwork teacher had three fingers on one hand and two on the other, and HE was teaching us!!
And that isn't a joke, it's perfectly true!!
Eddy
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It reminds me of my grammar school days - Our woodwork teacher had three fingers on one hand and two on the other, and HE was teaching us!!
And that isn't a joke, it's perfectly true!!
Eddy
Should have gone to spec savers - :hehe
Is the only Decent reply i can come up with to that one .
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It reminds me of my grammar school days - Our woodwork teacher had three fingers on one hand and two on the other, and HE was teaching us!!
And that isn't a joke, it's perfectly true!!
Eddy
Those who can do those who can't teach
Regards,
Gerald
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Geoff,
its interesting ,silver soldering is quite easy as long as the correct flux/solder is used,I do feel that anyone who wants to develop an interest in engineering cannot go wrong by starting with a simple pot boiler as there is very little in the way of equipment needed, a propane/butane mix torch,simple drill press and a bench grinder to make the flanged bushes,or you could go fancy and use a hand drill and a file (but be careful with the file) with the bush on a mandrel(tap and a securing nut)
with care a lathe is not needed.
then just a £10 pressure gauge and a garden sprayer for pressure test.
there is very little chance of a boiler blowing up!,just look at any mamod
and these are brass not copper......
Steven
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Managed to spend a day in the cellar, good progress. dry run assembly. Bushes soldered to end caps. Main tubes not soldered yet, waiting for son and his OXY-GAS torch, my MAPP torch will provide background heat. Geoff I hope I have attached over all view, one of each end and the displacement oiler.
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This shot in better focus. but the manafold is not so clear. G
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better attach it!
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Geoff,
at the risk of showing my complete lack of knowledge on this subject is there any chance of a quick layman's guide to what all the bits and pieces are, what they do & how they do it.
Appreciated,
Kim
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Steven let me know how the vertical boiler is progressing.
Kim, I am no expert but this is what I have read. On the gauge end of the boiler, right top is the round pressure gauge on a syphon, the bent piece of pipe. The syphon is to prevent damage to the gauge. On the left the glass tube is the water level gauge. Bottom right is the blow down valve, to empty the boiler. None of this is strictly necessary, a removable plug at the water level could give the level at the fill, but you can't add water when working. The pressure gauge just tells you when the engine has enough steam to start. By removing the safety valve and inverting, the boiler can be emptied. On the other end top is the steam pipe, the steam doesn't go straight through the manifold, it goes into the small pipe and a round the boiler, before retuning to the manifold. On the end of the manifold is the steam stop valve this holds the steam until working pressure is reached. Bottom right is the clack valve where water can be pumpted into the boiler when under pressure. This also has a lope of tube to heat the water before it enters the boiler proper On the left another blowdown valve. All that is really necessary is the steam pipe and this could come straight out. The displacement oiler has a small hole in the steam pipe as it passes through a little of the steam condenses, water being heavier than oil sinks to the bottom forcing oil in to the steam pipe and on to the engine. Hope this is OK. Geoff
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Sorry I forgot the most important fitting, On top center is the saftey valve this one is set at 28psi. Geoff
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The casing & funnel. R.G.Y.
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Don't tell the wife the back of her washing machine has a big hole in it!! R.G.Y.
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The latest had a test found 2 leaks had to re solder! OK now.
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latest. showing how the plant will look.
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Hi PD's........R.G.Y. ....do you line the interior surfaces of the boiler casing with refractory material for improved :coffee...... thermal heat retention?....Derek
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Yes Derek, I am going to use Themalight building block cut into thin strips. Because its cheap and available. Also the stainless shield will stop the heat going st right up the funnel. Geoff
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Hi PD's...& thanks RGY....this is a very interesting build thread :terrific
Your semi unconventional design.....but conventionally fired boiler will attain approx 150 degrees C surface temperature on the top singular shell
We see the stainless steel heat deflector plate @ the top...........however you could consider a few layers of aluminium foil over the Themalight material :crash .....the aluminium sheet will blacken even at these low temperatures, but look preferable to a blackened Themalight surface......Derek
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Derek, The last photo I posted is minus the mild steel top and side covers. If you go back to post 45 top photo, you can just see the top cover with the funnel attached and the screw holes for the sides. I have to make a new top as the funnel was to near the safty valve!! Plus the funnel needed for the model I have in mind is just forward of the paddle shaft. This is another advantage with a water tube boiler, the funnel can be possitioned where best for any model. If I change my mind and build a differant ship just replace the top. Thanks for the interest.
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Just waiting For the gas jets, then I can make and install the burners, and complete the insulation. By the way the pipe and fittings are made for refrigeration plants and are stronger than domestic water pipe. This is for Mat I know he was worried about the use of any old rubbish.
In the photo the new top cover needs a coat of paint (wood burner), the white paint from the washing machine just went brown when the gas torch was played on it, so that's OK. The wife hasn't notest the hole. Geoff
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Now it's all put together it looks like a very neat unit Geoff, well done!
Regards
Eddy
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Thanks Eddy, here is the complete plant. Now the difficult part finding someone to give me a certificate. The local model engineering club tester doesn't want to know not a railway engine!! and what to but it in. Geoff
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Hi Geoff,
Over here in Ontario Canada you would not need a certificate for a boiler that size. Can you do a video of it under steam?
Regards,
Gerald.
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Gerald, sadly there are to many rules here. As I will have to sail in a public place I will need insurance for that I need the certificate. The insurance company will do it for £ 450!! This size boiler need only be tested the once. Visited B.C. eighth times plenty of sailing waters there. Is it the same in Ontario. The engine has run on air but still waiting for the gas jets for the burners. I could play a blow lamp on it I suppose. But haven't started on a boat yet so no rush. Geoff
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The jets have arrived. Change of plan only one burner but holes on each side. See below. Cuting and instaling insulation. Driling the burner and fireing up the flames just visable in the last photo. Geoff
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Geoff, I have been following this thread with interest, and I am fascinated to see the boiler and engine working. I am not totally convinced you have managed to make a lower profile boiler, but you certainly have taken a different approach and one that almost anyone could also take, brilliant.
Neil
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Neil thanks for your comments. You are right the profile of the boiler casing is higher if anything. But the center of gravity I believe is lower than a yarrow 2 small tubes at the bottom and most of the water in the tube above. If you study a scotch boiler most of the lower quarter is narrow and taken up by the fire tube, not much weight of water. As you say It is simple to calculate no stays narrow tubes so thinner copper can be use with complete safety. Some domestic pluming pipe can be very thin so beware, the pipe used for refrigeration is best as it has to withstand up to 40 bar. There is extra work in the case but is required to be accurate . Still have the insulation to complete and I'm still playing with the burner, drilled out the jet .3mm and extra 9 holes in tube, 29 total. running soon, but won't be(allowed) in the workshop over the next few days.Geoff
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That should read. case need not be accurate. Geoff
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Geoff,
you are doing a lovely job,its nice to see the boiler comming along,
I have not had time to finish my MB22 engine but have 2 weeks off so might get chance
then make my own boiler,its always nice to see ones own work come to life.
btw yellow ends to the flame is not enough primary air in the mixing chamber,
which leads to co2 production.
please can you tell me the bar litres or your boiler or mls and working pressure as I am trying
to get enough info to ask a model boiler tester why you have to resort to an insurance company my info suggests you should not have to.seeing as I work with model boilers
I am in a position to ask.
Regards
Steven
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Steven, I through I wouldn't get into the workshop over Christmas how wrong. Christmas day assembling all the toys, boxing day repairing them.
My boilers total capacity .4 of Liter working pressure 2 Bar max
= .8 bar-liters. The reason it's so small is,that is all the pipe I had at the time. One inch pipe 36inches long = .5 liters. Eighteen inches =.25 liters The reason for the certificate it is a club requirement on our sailing water in a theme park.
Yes I am having trouble with the burner, when I increase the air some of the flames go out. I drilled out a jet .03mm then the flame started is burn about an inch from the hole, and some flame out again. I think the hols are to small. So I plan to solder a strip of brass over the existing holes to increase the thickness of the pipe. As I have read that the holes should not more than the thickness of the tube. Dose that sound right to you. Geoff. Or any one else.
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We need Sandy C, or Bogs.
regards,
Gerald.
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Hi Geoff,
your gas system
gas need a certain amount of air to burn so yellow tips indicate too much gas
the thing to do is where the jet is located should be some air holes file these out
carefully to bring about the blue flame,
now you should have a flame only just above the metal tube , now I am not the best for
your type of burner but, now you have increased the size of the jet you will have too
much velocity of gas and air hense the 1" flame
so you need to throttle back the velocity.ie a finer needle jet on the tap or change the jet.
on my burner tube I have 2 holes and the jet is placed inside these holes if you make the jet movable then you can vary the position of the jet while in use.
try it sometime it is quite apparent what happens to the flames
if you get the gas velocity too slow it will burn back inside the burner if the plate is
too thin or it will just go out.
increasing the hole size i my opinion is not the best option instead slit the hole so it is fan shaped this is normal for 16mm gauge internally fired locos and works very well.
normally I believe a number 3 or 5 jet is used for your type of burner
I use a numer 8 jet for my ceramic burners
if reading correctly (0.3) you have a number 12 which I feel is far to large
and you may have to replace it.
Number 3 which has a 0.15mm dia jet bore
Number 5 which has a 0.2mm dia jet bore
Number 8 which has a 0.25mm dia jet bore
Number 12 which has a 0.3mm dia jet bore
Number 16 which has a 0.35mm dia jet bore
had chance to run my MB22 engine on air( cycle pump) so even I got time to play.
Thanks for the boiler info
I will agree with the .8 bar litre
should be pressure tested to 2x working pressure or 4 bar nearly 60 psi
I will have to ask to how much the steam test is, figure I have here is not more than 10% rise.
when I return to work I will be asking many questions as
under 3 bar litres I am sure it does not come under the CE ruling,the wording I have
is "best engineering practise" but we will see.
Regards
Steven
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Hi PD's....& yes Gerald...I too would sincerely love it if we could get Sandy Campbell & bogstandard back posting as they did :no1b
I am sure both gentleman posted words to the effect ....'that a yellow to red flame is a carburising flame principally caused by a lack of oxygen & hence incomplete combustion'
Again from memory it is the venturi we are creating to draw the optimal amount of air [oxygen] into the gas path & hence the bluish tipped flames
I have had to format my PC C drive so have lost many of my favourites.....but we recently had a few postings from an Australian engine & boiler manufacturer.......in their Melbourne WEB page was an interesting procedure detailed out for setting the burner flame height...... :thinking
Derek
PS ....here is that site......http://www.modelcomponents.com.au/
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Good imformation thank you all. I have air holes just behind the jet they were not clear on the last photo. (see the latest, the ajuster is hxeagonal). I was just too impasant it is now a lot better. Derek will be pleased to know it will be instaled in a rat infested hulk. Geoff
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Geoff,
looks like you have it working now
well done.
burners are always a little finicky
Regards
Steven
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Seven, Yes I kept the bigger burner drilled another row of holes on the top reducing the gas pressure. The flames are longer than shown, the gas had almost run out by the time I had the camera ready. Geoff
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I have worked out my costs for the boiler. £140 I did acquire a lot of it for nothing it's true but but if every thing had been purchased I don't think it would have exceeded £200. Roll on the new year I can get back in the shop.Geoff
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I am now building the model to flt it in. So the posts will be in construction ( Duke of Devonshire) from now on. R.G.Y.
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Well one more post, Eddy said things have been too quiet of late. the boiler and engine in the Hull. Geoff
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Good news, on seeing my boiler in the flesh the club boiler inspector said no problem. Bring it to the test day and it will be tested. He was ether impressed or he things it will fail!!! Geoff
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I have made a new burner for this boiler. Had trouble keeping the holes near the jet alight. After numerous attempts to get the mix right and the length of flame. I thought the problem was the tube was to small a diameter at 1/2". The new 5/8" tube has cured the problem. I have also moved the holes down the tube by 20 degrees, this plates the flame to the base of the boiler tubes. Geoff
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My experiments with evening the flame length of the Accucraft poker burner (less than 1/2" diameter): The velocity of the gas is too great as the gas/air mixture enters the poker. The result is that the flame is long at the end of the poker, and short at the start. Fast gas has low pressure, slow gas has higher pressure - as the gas hits the closed end of the poker, it slows, the pressure increases, and the gas shoots out of the slots making a high flame. This can be cured by inserting a turbulator of some sort into the poker. The resistance provided by the turbulator slows the gas, increasing it's pressure (pressure and velocity are inversely corrolated). My turbulator is simply a twist of metal screen slid into the poker; fancier ones are cone-shaped with roughening grooves.
So, a narrow diameter poker can be made to light along it's entire length if the gas is slowed as it enters the poker.
A more elegant solution, used by commercial gas appliances, is to make the poker conical in section instead of cylindrical (wide end of the cone at the far end of the poker). This automatically slows the gas as it enters the poker, the opposite phenomenon to a garden hose nozzle (which narrows, and trades water pressure for higher water velocity).
Hope this helps.
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Brooks, That explains it. The larger tube is OK for this boiler. If I need a smaller one again I will bear this in mind. Thank you. R.G.Y.
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Hi,
I just found this interesting thread. This boiler design looks really interesting. The book mentioned in the first post, MODEL BOILERS AND BOILER MAKING by K.N.HARRIS, does this include instructions on the calculations required to design and produce such a boiler?
Thanks
Ian
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Ian, The book contains formula for calculating the strength of matirials, and the constrution of meany boilers but not the "Wedge" boiler. It taught me enough to build my own. Geoff
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Will be replacing the insulation on this boiler. See the Duke of Devonshire thread. R.G.Y.
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I am lighting up the boiler at last. Please all you knowledgeable people who have offered advice in the past. Go to construction Duke of Devonshire. I would value your input. R.G.Y.