How dopey is this traction engine project?

[The Artful Bodger]

I would like to build a mobile steam machine but not too small, something that I can drive or ride around a little. Steam bicycle, steam buggy, maybe.

However what I would really like to do is a traction engine but the projects I see on line have taken their makers decades and the kits of casting for some cost more than a couple of new cars.

So.... and here is the (maybe) dopey bit.... for novelty and ease of building I could scale UP something like a Mamod traction engine? ;D

 

[Metal Butcher]

How about a steam powered bicycle? By converting an existing bike you would save a lot of time making the project go much faster. You could build the engine from scratch, or from a casting kit called the 'Vesuvius".

[ame]http://www.youtube.com/watch?v=dqBKRo8q3rQ[/ame]

http://www.steamautomobile.com/phorum5214/read.php?1,6306,6313

-MB

 

[Jasonb]

If you upped the Mamod you would need a lot of fuel tablets ;D

At a size capable of pulling you it would be a very inefficient design, you would also have quite short runs as there is no way of getting water into the boiler while its running to replace that lost as steam, steering down the chimney would be a job if sitting on a trailer, etc.

Something like the Minnie in my Avitar is quite often doubled up to 2" (1/6thscale) and is capable of pulling two adults. It can be made with no or very few castings - flywheeland cylinder being teh two I would suggest. You could also simplify parts or modify to suit what you have on hand.

Other options could be something like this, garden tractor chasis, vertical boiler and a steam engine, not the best looking but it flys around the rally fields as it retains the clutch & 3 speed box of the tractor.

J

 

[The Artful Bodger]

How about a steam powered bicycle? By converting an existing bike you would save a lot of time making the project go much faster. You could build the engine from scratch, or from a casting kit called the 'Vesuvius".

http://www.youtube.com/watch?v=dqBKRo8q3rQ

http://www.steamautomobile.com/phorum5214/read.php?1,6306,6313

-MB

Thanks MB, a steampowered bicycle is on the list although I cannot guarantee it will ever get any further than that!

 

[The Artful Bodger]

Thanks Jason, can you tell me more about the availablity of casting for the Minnie?

John

 

[The Artful Bodger]

OK Jason, I did a bit of searching and found a wealth of stuff related to the Minnie, thanks.

Now then, back to the Mamod. It would be interesting to know how the total number of Mamod traction engine made compares with the makers of any full size machines? I suspect it would show up very well and should by that alone be worthy of 'modelling'! :big:

A bigger Mamod would need a better fire and boiler system, including that feed pump that Jason mentioned, steering would also have to be sorted out but the essential visual characteristics of the Mamod could be duplicated I think.

Oscillating cylinder, but enhanced a little to be double acting and the belt drive around one wheel could be a heavy vee belt.

This raises the questions though, has anyone ever built a model of a Mamod machine? Something like 2'6" scale maybe?

 

[Jasonb]

Blackgates do the 2" Minnie castings, I can scan a pic of the pricelist if you need it. If you are in NZ postage will be high but as I said you don't really need most of teh castings. Sign up for this traction engine forum and have a look at this build thread, hes making most bits himself.

http://www.tractiontalkforum.com/showthread.php?t=8883

Back to the mamod, I don't think a vee belt would be the way to go. One to get the tension you will be putting quite a lot of load onto teh bearings and secondly you want about a 16:1 low ration which would likely end up with a big back wheel. Chain & sproket would be better, a few original engines had these. I would still try to get two ratio's in, the 16:1 for manovering & rough ground and say 10:1 for running on good surfaces. You also want to be able to run the engine while stationary so the blast pipe can be used to draw the fire and for the same reason a blower will need plumbing in.

Other problems with keeping it looking like a Mamod would be:
Mamod axle passes through firebox, traction engines don't though a few portables had this set up
Mamod does not have a tender, you will need this for some water & coal
Mamod has no ashpan or damper to control fire
Working smokebox door required to clean tubes
You will want something more substantial to hold the crank and intermediate gear shafts
Water gauge, pressure gauge, 2nd means of filling boiler such as injector
parking brake
Oscillating engine may not run slow enough.
Etc, etc.

J

 

[The Artful Bodger]

Thanks for that information Jason, I will check out the tractiontalkforum directly.

Yes, I can see it might be quite a challenge to make something recognisable as a super model of a Mamod!