Steam powered tonka truck

[scalebowler]

Tried out the boiler tonight but did not have denatured alcohol so I (stupidly) decided to use rubbing alcohol instead. Really stupid idea and I knew better but was dumb enough to do it anyway.  Never really heated up enough to make a lot of steam and put a thick layer of nasty soot on the boiler. It was so bad I had to use baking soda and a tooth brush to get it scrubbed off. Not doing that again. Will let you guys know when I get a real test on steam just as soon as I get some alcohol for it.

[scalebowler]

Did a run on steam tonight to see how the engine worked and I am kind of dissapointed. Turns out the engine is not as powerful as I hoped and now I am not sure if the engine can run the truck. Now I have to figure out if I want to keep messing with this engine or if I want to just put the engine I made away and make a larger and more powerful engine.

[mznb1u]

Just install a Mr. Fusion!  But seriously, you have a lot of time and energy into that project.  I hope it comes together!

  Tim

[scalebowler]

Just install a Mr. Fusion!   But seriously, you have a lot of time and energy into that project.  I hope it comes together!

  Tim

Haha! You know the people at school kept making back to the future jokes about my truck and one of my coworkers kept asking where the flux capacitor went.

I hope to do get the thing running some day. I am seriously thinking about going out and buying a pre made cylinder and piston assembly now and just building the parts to adapt it to my truck since I know that the specific one I am thinking of getting is designed to run a model steam powered tractor or a model steam powered car so it should work although after building an engine from scratch it kind of feels like cheating. Also think that I might have to rebuild the frame and jack up the suspension a little bit to make room for everything. Need a total redesign of everything besides the boiler and firebox if I want this thing to work.

[Creighton]

Smaller truck?
Creighton

[scalebowler]

Smaller truck?
Creighton

Maybe but I would then have to get a new boiler and firebox and find a truck that I could do that with (and I kind of have put a little too much money into this truck so I don't really want to get a new one just yet). Really leaning towards the pre made piston and cylinder idea since the boiler would be about the right size for the cylinder assembly that I am looking at getting. I think the best thing to do would be to remake the burner with some thicker brass strip (over thought the last one), get the cylinder and piston and make a mounting plate for it since the company that I buy parts from does not seem to stock that but it is only a flat piece with a few holes drilled in it so I think I can handle that, I have to remake the crankshaft which is actually not too hard since all I have to do is turn a piece of steel down to the right size and then cut the two outside parts out on the milling machine, make a new flywheel and make a few shafts with some pulleys on them to gear down the motor and hopefully get some more torque out of the new engine. I don't have any classes this summer so I might just spend it redesigning everything else. It sounds like a lot of stuff but the more I think about it there are really maybe only 4 main parts to this truck and I only have to redo 3 of them.

[Ken R]

Say, it seems as though it would be easy enough to get some power out of a steam engine that size to make it run.  I don't know the physics behind steam, but to consider the small size of a steam engine on the stanley steemer compared to the size of the vehicle, it would seem there's a mathematical solution to the amount of power that can be pulled from a steam engine relative to the steam input, piston size, stroke length, etc.  If I have time tonight, I'll do some research and see if I can come up with any ideas for you.  Not to say that you haven't already done all that, not to insult your intel by any means.  You've done such a wonderful job and it took me a while to make it through all your pictures, I'd hate to see you give it up!!!  Like the others, I'd love to see you make it work!!!!

Ken

[Creighton]

I did a search for some basic calcs awhile back. Didn't find much at this scale. Anything you can find would be great!

Alex, correct me if I'm wrong but think the issue with steam is high pressure and temp is required to make real torque. Hard to do with a small firebox.

The Stanley Steamers were very cool.
http://www.stanleymotorcarriage.com/GeneralTechnical/GeneralTechnical.htm

Creighton
   

[scalebowler]

I did a search for some basic calcs awhile back. Didn't find much at this scale. Anything you can find would be great!

Alex, correct me if I'm wrong but think the issue with steam is high pressure and temp is required to make real torque. Hard to do with a small firebox.

The Stanley Steamers were very cool.
http://www.stanleymotorcarriage.com/GeneralTechnical/GeneralTechnical.htm

Creighton
   

I think the main problems with my design is the construction of the engine (I think some of the stuff is off a little bit) and the axle. Mostly I based the design off of an existing design which was for a much smaller vehicle and when looking at some of the engines that could power this model I noticed that the piston is larger than the one I have in my engine and I also noticed that some of the model steam cars had a set of belts and pulleys to gear down the engine and get more torque. I know I can get this thing to work I just need to spend some thinking this through. I do think I got the burner problem figured out. I have been looking at a lot of ebay auctions for model steam powered cars and tractors and have been using the pictures that the seller put up to get ideas on how the companies that make these things make theirs work. I really think that I could get this thing to work if I got the parts designed right and used a few pre made parts (Really leaning towards the pre made piston and cylinder so that I don't have to buy more brass since that stuff is extremley expensive!)

[scalebowler]

I think I got the engine design figured out! Check out the 2:00 mark of this video and it shows an engine that is using the cylinder and piston assembly that I am planning on buying http://www.youtube.com/watch?v=xCbu3w14fw0&feature=related All I would have to do is recreate the frame of the engine and get a flywheel and do a little bit of work with some pulleys but if that engine there can drive that model steam roller (which weighs close to 4 lbs) then I think that same design might work for me.