Paddleducks
Other Marine Models => Live steam => Topic started by: Fred Graham on August 02, 2008, 06:31:05 AM
-
Hi, Andy and Ian,
The guys to be jealous of are the ones who have boats that run at these speeds. Trying to get video was a real nightmare. I startedoff near to the edge but once the boat built up speed it was only takin 5-6 seconds to make one lap and the 6 foot wall of water made it quite exiting. I will be going back to see them again and hopefully will get some pictures at speed but it aint easy.
At present the record breaker is 'in the pits' due to lube problems. He usrs the highest temperature steam oil with a castrol additive which is hard to get these days. He uses hydrostatic lubrication which utilises water feed pump pressure to force lube oil into the cylinder. There is a write of Bob's boat in model engineer. If there is an interest in this I will dig out the reference dates.
-
Hi,
Oops duplication again on my last post. I wanted you to see the engine so I'll have another go. I hope its in this time.
All the best, Fred Graham
-
Hi PD's....well Fred.....I see a nicely planked hull on genuine 5 ply hull frames.....but cannot figure out what that monstrosity of an engine it is..... :shoot
I see straight cut spur gears.. :hammer...a few copper lines....at tank of some sort & lots of socket head cap screws with a little insulation material
Ian mentioned flash steam... :bravo but I am :squareone....tell us more ..........Derek
-
Derek, a Flash Steam boiler is not a water vessel as conventional boiler is but instead a tightly wound coil of pipe, sometimes two layers. Water from a tank is pumped through it by an engine driven waterpump. A very powerful blowlamp, usually petrol burning in the old days, superheats the water/steam as it progresses through the "boiler" resulting in very hot, very high pressure steam. The engine is usually fairly conventional, in fact the A H Rayman "High Speed Steam Engine" in my paddler came with plans for both conventional and flash boilers. One day maybe I w2ill get brave enough to try building a boat with the flash version. I believe they are very noisy, louder than an I C engine. A steam hydro like the one in Freds posts is capable of around 100mph while tethered to a pole - AWESOME!
-
Hi Derek and Kiwimodeller
You are dead right both of you., although Kiwimodeller is slightly kinder, "Monstrosity indeed!" Its a work of dedication by a keen exponent of flash steam and I kinda thought it was quite good looking.
Actually joking apart it is single cylinder 1 3/16" bore x1" stroke uniflow sinle acting engine with poppet inlet valve. Ihas a water pump 1/4" x 1/2" maximum stroke and a fuel pump (Parafin/petrol mix) which feeds a triple burner. The burner heats a complex coil of stainless steel tube !/4" I think and approximately about 30 ft of it.
It generates a phenomenal torque which takes a great deal of holding back and if not tethered to a central pole around which it laps it might well go into orbit.
I have watched and if anyone is in doubt about the quality of the engineering, the dedication to his hobby and the engineering skil expended to achieve a world record in this class they really ought to see the model on the pond.
I think I may be slightly biased!?
All the best to you both, Fred Graham
-
Hi PD's....& we should really take this thread elsewhere :whistle...but was it not Von Braun.....[Werner] that considered the potential of flash steam :ranting :ranting :ranting :ranting :ranting and converted the energy concept into rocketry...or as we now know high speed baby gas turbines?....did they not power the original V1 & V2 rockets in the late 1940's.......& we still have them for use in current TSAMS or ICBM launchers :shhh :crash ......
So Fred & Ian......having seen all of this ,,,,, :gathering,,,,,,,I will take my older bones & stay with low speed piston valve steam engines...Derek
-
Hi Derek,
Sorry to have offended your "old bones", I myself am 67 old years but try to keep an open mind about anything on steam especially record breaking stuff.
You are probably right that it should be in different slot somewhere, but being a 'newbie' I did not know where. I suppose Mr Admin will know.
There must be someone in Paddleducks who finds 'flash steam' interesting?
By the way there is an interesting article in Model Boats this month (September) by Peter Arnott on LPG Vaporisers. Helping to keep the fuel tanks from cooling. I am sure that PD's will be interested in that, even you Derek (No offense meant).
All the best, Fred Graham
-
Hi PD's....& :hehe...you could never offend an OZIE Fred...we are unoffendable ...we eat iron ore sandwiches & wash them down with a :beer ...& we take a garlic flavoured fishoil tablet each day so we don't rust :whistle
I thought that Jim :crash would have moooved this steam thread into the Live Steam folder.............where all good steam stories live.....Derek
-
Hi PD's....& :hehe...you could never offend an OZIE Fred...we are unoffendable ...we eat iron ore sandwiches & wash them down with a :beer ...& we take a garlic flavoured fishoil tablet each day so we don't rust :whistle
Derek is correct Fred - I've tried to offend Aussies in the past and they've all fallen on stoney ground (only joking!)... Iron ore sandwiches and :beer is what the Scots call Iron Bru - Well that's what Aussie lager tastes like to me! :hehe
As Jim has started to deal with this, I'll leave it to him to move the topic into the Live Steam folder...
Eddy
-
Hello all, OK I'm an idiot I must have been fast asleep when I tried to move the topic earlier :whistle now back on track
cheers
Jim
-
Hi PD's....& seriously Fred...this is typical of the help from our PD moderators......& also the fun & banter along the road.....
Flash steam is a very interesting subject :terrific & will be read & re-read by many around the globe ...including me
Opps......it is Sunday morning ..... 10.06 am here in OZ....time for a :coffee & a glarlic+fishoil tablet.....
Thankyou Jim......thankyou Eddy........ :nahnah Derek
-
Hi Derek,
What no Vegemite with that!
At one time they ran Flash Steam and round the pole here, but it was well before my time.
Hi Fred and welcome aboard, Thanks for the heads up on the Sept. Model Boats, if Peter Arnott has an article I will try to find a copy. The closest I have come to Flash Steam is building Pop Pop engines, and one time I had a water pickup blocked on a Gas boat witch on slowing down became unblocked, with a large plume of steam.
Regards,
Gerald
-
Just to keep Derek happy I will add my two new pence worth.
The only iron Derek eats, is when he is trying to chew the manacles off his convict stock ankles and wrists. :squareone
As for the Aussie beer. How? Where do they grow all the finest hops to brew it?, in the insect infested desert they live in?. Methinks they have rather large chemical plants to make the stuff. :shhh No wonder they all have addled brains. :beer :whistle :nahnah
To get back to the matter of flash steam.
It is definitely a dying art form in most places. I personally think it is all due to the decline of the combined model maker/machinist. In the early days, the only way to make such high powered beasts, was to make the engines yourself either from back street castings or bar stock. Over the years, the meaning of model making has changed, at one time you would have to make everything yourself, nowadays a lot of it is bought off the shelf. Unfortunately flash steam isn't included in money making company's scheme of things, so it is left to the diehards of the modelling fraternity to carry on using the remnants of a golden age. As far as I can see, engine and boiler design has changed very little since the beginning, just better fuels, materials and tighter tolerances of the machining, so giving the edge over older power plants. Or are totally new designs being made?
Does anyone else have any views on this dying part of our fascinating hobby. Maybe I am totally wrong in my views, it wouldn't be the first time, or is it environmental issues that are causing the decline?
John
-
I think your partially right John..... There are very few people who want to put the effort into making their own engines and boilers nowadays, add to that the expense of the machinery needed to do it, nevermind the skills required!
Then we come to the "nanny" state we now live in (certainly in the UK), where there are so many rules and regulations it's impossible to keep up with them all :(
The same is true of modelling in general - Youngsters today are used to instant results..... They have grown up with computers, MP3 players, Games consoles, etc etc.... Plug it in and go..... If it requires a few months (or years) of effort they don't want to know!
And how many times have you seen the "green" lobby say that something will cause pollution, or excessive noise, or whatever - Without ever investigating wether their comments actually have any validity?
Sorry, it's been a bad day! Rant over.... But I'm sure you get my drift?
Eddy
-
Hi Folks,
Oh dear, shame about the kids but all the apprenticeships must be in India and China so they have little chance to get the skills I guess. Pity, 'cos there's lots of fun and satisfaction to be got from playing in workshops.
I have a Myford Super seven bought 50 years ago brand new for less the £70 and that beautiful new Conioseur (Spelling?) costs more than £7000. Trouble is if I changed it all my chucks and collets fit directly on my dividing head on my miller (also a Myford) so it would be a pain in cash and changeover.
I love the picture of Jim King and his flash boat Gerald, those were the days.
Do you think they've heard about 'Old Peculiar in Oz or NZ 'cos I agree this amber nectar is like the reindeer pee that comes from Scandinavia.
All the best, Fred
-
Hi,
I have successfully constructed a flash boiler, which is being used to steam a Stuart D10 machined from the castings kit. The D10 is connected to a small DC generator acting as a controllable load.
The entire system is controlled by a home built and programmed control system based on PIC micro-controllers. The control system receives the engine RPM demand signal from the radio control receiver and controls the electric feed pump and servo-controlled gas valve. The actual engine speed is measured and the feed pumps and gas valve are automatically adjusted to maintain the required speed.
I have just perfected the method of starting (and stopping!) the engine and find the RPM and temperature controls do a find job - good speed change response and steam temperature controlled well below 200C. No exessively high pressure or temperatures as experienced with the old classic flash steam boats.
To give an idea of the software complexity, it has taken me at least five times the hours to write the software as it did to build the boiler and engine - not for the faint-hearted. Being a software based control system it is very easy to duplicate additional systems.
My next step is to build a simple hull (5 to 6ft) and get the lot onto the lake for additional testing.
I will keep you posted.
All the best -Ian
-
Hello all, Ian an excellent and informative post from a dedicated engineer. It takes real enthusiasm and passion to complete such a complex design to this stage.
cheers
Jim
-
Goy any photographs Ian? I'm sure a lot of our steam guys would find it interesting to look at...
Regards
Eddy
-
Hi Ian,
Which PIC micro?
Regards,
Gerald
-
Hi,
Thankyou for your enthusiastic responses.
The control system uses a number of MicroChip 16F877 PICs selected because they have a good number of analogue inputs and digital inputs/outputs and a flash memory (hence my login name flashtwo - flash steam + flash memory). The analogue inputs receive the pressures and temperatures signals of the development steam plant, which are used for control and indication. The digitals are used to drive servos and the Electronic Speed Controllers (ESCs) for the electric water pumps. The PICs also drive an LCD display and control box which is removed when it is not required for development.
The actual boiler comprises 5 metres, 1/4" copper pipe doubled coiled into a 10" long by 4" diameter horizontal stainless steel enclosure; this was based on the designs in the book 'Experimental Flash Steam' by Benson & Rayman.
The steam outlet pipe connects to a small manifold from which the pressure and temperature are measured. The manifold also has a small safety valve set at 7Bar. The steam then goes directly to the Stuart D10 without the need of a regulating/throttle valve, steam flow being controlled purely by the feed pumps (I am using two for anticipated reliablity out on the lake) and the gas valve.
The boiler stack contains a metre or so of 3/16" copper tube acting as an economiser which can raise the feed water by about 50C.
The boiler and engine can be running from cold in a couple of minutes, since the boiler tube only contains about 35 milli-litres (yes 35ml!) of water and hence the need of a reliable feed pump. The small thermal inertia of the boiler is one of the reasons why a steam regulator is not required, since the boiler responds very quickly to the gas valve movement.
The control system is built into a slim box and is designed to be transferable between models since it plugs into a simple interface board which resides on each model boat. Currently the controller contains six 16F877s - one of them is redundent and three of them can be replaced with smaller/cheaper PICs; of the remaining pair, one controls the gas valve and the other the two water pumps.
I shall post some photographs once I've tidied the workbench and mopped up the steam oil!
All the best
Ian.
-
Your boiler control system seems very interesting. I'd love to see some pictures too.
-
OK PD's....I will send all of my left over 5 cent coins to "Life Line" here in OZ if .....All the best Ian. shows the colour of his thoughts............... :beer
-
Hi Ian,
It sounds fantastic. Could you post the schematics and source code for the control unit too?
Regards,
Gerald.
PS I have bought the PIC kit 2 programmer and just started playing with it.
-
Dear Derek,
(I've been looking forward to this moment!)
Please send lots and lots of your left over 5 cent coins (and dollars) to "Life Line" ( http://www.lifeline.org.au/support_us/donate ).
The flash steam computer controlled test vessel, the "Vital Byte", made it's maiden voyage on Saturday
at the "Model Boat Meyhem" meeting here in England (see their website http://www.modelboatmayhem.co.uk/forum/index.php?topic=15817.25 for my account of the maiden voyage).
It was very successful and will now will tuned up to "water skiing" performance (not at 32kg displacement though!).
Thanks for the challenge!
All the very best
Ian.
-
Hi all......a quote from Ian.......
"I had trouble starting since the new gas cylinder pressure was 3.4bar (the cylinder had been in the car under the hot sun)"
Congratulations of the maiden voyage working so well & full credit to you ....I have trouble with our new kitchen microwave .......gone are the days of a knob to set the temperature & a dial to determine the minutes.......
:picknose,,,,,,now you need a Degree in computing science to boil water :breakcomp ......Derek
-
Hi Ian,
I would like to see some pictures of the flash steam boiler and the boat!
Tom
-
Hi Tom,
I had enough on my plate preparing for the maiden voyage to remember to take a camera to the event, but it was recorded by other people.
On the website http://www.john-dowd.co.uk/ there is a YouTube video and I'm chatting about the boat and controls from 2mins 11secs into the video.
If you go to the website http://www.modelboatmayhem.co.uk/forum/index.php?topic=15817.0 , you will see photographs of the steam plant in various stages of development. You will have to register to gain access to the photos and I would post them on this forum if it was a bit easier to do.
Derek - you have to understand that the plant controls were developed in our winter when the shed temperatures were around 2degC and the aim was to maintain gas burner control under those conditions. It was very hot last Sunday, around 21degC, and even hotter in the car! I shall have "Australianise" the software for higher ambient, especially for all this global warming thats predicted. Have you posted your donations yet? Thanks for your congrats though - its very much appreciated.
cheers
Ian.
-
I would post them on this forum if it was a bit easier to do.
Posting photos on here is exactly the same as Mayhem as we both use the same forum software...... Takes all of a few seconds to post an image....
-
Thanks Eddy - that makes life much easier.
Ian G.
-
Hi,
Here are few photos taken by Alan Poole of the Dover Model Boats Association last weekend with the above steam plant mounted in the experimental boat the "Vital Byte".
Ian.
-
And another.