Traction Engine (Electric)

Have a look at this recent thread about batteries to make steam

Ron, there are several 4" scale wooden/metal constructed traction engines about, driven by mobility scooter power trains, they look good, will pull a trailer and are clean at the point of use. At least one has been built to the Burrell drawings to my knowledge.

Chris Gunn

Thanks Chris, I guessed that there would be electric traction engines around as most things have been electrified be it loco,s, traction engines, boats, r/c planes etc etc. I am still undecided as to whether I will have a go at one as my next project. I dare say I probably will at some point but a class 22 may well be what I design and build next.

Nigel, I love steam engines and whatever they power but apart from the basics I have very little understanding of all their workings. I also dont know much about heating water with battery power but my gut feeling tells me that you would need a lot of battery power, wouldnt gas be a more viable option...just a thought, I could well be wrong.

Ron

You are not wrong Ron, generating steam for model locomotives or traction engines using batteries as a power source is really not practical at this time. Maybe in future as batteries develop, but not today.

Now if you could devise a compact fusion or fission reactor for models, that might be a different story. Fuel and containment might be a bit of a problem though.

For now, gas or coal firing are probably still the most practical ways to generate steam in mobile models. High energy density in a low volume of fuel, and efficient heat transfer. Several companies have offered commercial steam boilers for stationary models that are mains electricity powered with a tubular element or cartridge heater. Trailing a high amperage power cord at a traction engine rally would likely be frowned on, and running mains power through the rails for an electric powered large scale steam locomotive boiler could be interesting if someone or some metal touched both rails....NOT suggesting this at all as something to try, just joking.

Thanks for the comments about power density. I’m not thinking about serious rallying but just a minnie primarily for display that may occasionally be steamed for a brief run across the garden. I figure that if it was flushed through with boiling water to pre-heat it then filled with more boiling water before the heater was turned on I might be in with a chance.

No way Nigel, powering a steam engine by battery power is not too far short of the idea of perpetual motion. A better idea is use the battery, and the motor and gear box section of the battery drill, the motor could be hidden under the coal in the tender, and the battery rearranged to fit in the boiler.

Ian S C

I know some traction engines had generators fitted, I think showman engines did. Were the generators belt driven from the flywheel, I saw a picture and thats how it looked. Did any have any other means of drive or were they all front mounted and flywheel driven.

Ron

One of the reasons for having a traction engine run off an electric motor and battery power is that there won't be a need for a boiler certificate!

I started building a 2" scale Fowler ploughing engine to the John Haining design about 21 years ago and the first thing I did was the boiler. I had it welded in steel, a really nice job by a chap in the local engineering works. However not all of the plate material was traceable and neither was the welder's coded credentials. Oh dear!

Two house moves later and the job has remained stalled ever since. My plan now is to incorporate a dc motor and gearbox in the boiler shell and connect that to the crank drive above. The boiler tubes never got finished anyway so basically there is an empty shell to work in. The batteries would go in the driver's seat carriage.

It's still a job for the future (retirement?) but definitely on the 'to-do' list. Working on at least two other major projects before that.

Would anyone be able to tell me the approx diameter and length of the boiler on a 2 inch Minnie, also the fire box basic dimensions. If I go with a simplified engine I would base it on a Minnie and need the dimensions to calculate the fit of one or two items.

Thanks

Ron

My planned next project a class 22 loco will have to wait I have decided to build a traction engine and as per the theme of this thread it will be electric powered. Even if I wanted I couldnt build a scale engine, I couldnt afford it, I dont have the time, wouldnt want to spend years on one and never finish it. Also I dont have the skill and I dont have the tooling.

So the engine I intend to build will be a freelance non scale stand off representation of a traction engine. It will have the main features but be basic and simplified to suit what bit of skill I have and my tooling, the tooling I hope will improve though as I go along. At the moment I dont plan on using any castings and "wait for it" I also have no drawings. Well I do have one or two general drawings which I downloaded to get some idea of sizes and I have studied hundreds of photos. So a lot of parts will have to be my own working sketches and sizes based on the photos and the scale.

The scale I have decided on is an inch and five eights a bit odd I know but one inch is too small for me and two inch a bit too big. One thing for certain, it will be a challenge and a pretty steep learning curve but I am looking forward to giving it a go, apart from the wheels that is, at the moment they look a bit daunting..lol

So there we go, am I mad..? probably but we will see.

Ron

Not mad at all or so are a lot of us.. On my electric traction engine the battery was in the ride on trailer pulled behind. That way you can use a bigger battery, car? A small battery under the coal powered a sound system. No not a boombox...

Its good to know that I am not on my own then John.

Early days but I am considering a couple of options re the motor and battery, one would be to do as you have done and carry a 12volt in the trailer. The other which is a bit more upmarket but would keep the engine self contained is a brushless motor and lipo batteries. I think a largish R/C truck motor, probably an outrunner running off a 4S or 5S 30C 5000 mah pack would have plenty of power and good duration. The beauty of a traction engine of course is the low gearing which lends itself ideally to an electric motor drive.

Ron