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i want to design a small Stirling engine..

but am a bit confused..
i need a small engine, easy to construct, but i need power..
yes i need power..
i need this engine to move itself for at leaset 10 meters..

what do i work on:
- alfa type
- betta type
- gamma type
- rotary type ( i like this one, will it work?)

thanks

Designing a small Stirling engine with signifigant power output is a pretty big task for a beginner. Go to and check out the tutorial on S.E.'s. After that look at the plans available there.
Your request would be easier to fulfill if you told me exactly how you intend to use the engine and your overall goal. Is this for a science fair project? or what? Is it something that you have to design from scratch?

well it is kind of a scinece fair project..
actually it is for my mechanical lab class..
the aim is to make this engine i design (not necesarily froms scratch) to move itslf about 10 meters..
no need for high speed..
but am still not sure which type to select..

What energy source are you intending to use? Depending on power output and weight I imagine you'd need some kind of a clutch to start it moving.

question: How can I use available technology to move the engine itself for 10 meters?

answer: This site has MM-1, and MM-7 model size Stirling engines. A plug for the site, I will use them for example. *smiles*

Take one of these engines, your choice. The MM-7 looks like the machinerey might be more appropriate for the task, but maybe a bit more difficult to attach something to extract power. I think it is rated higher or something, meaning you need all the torque you can get, because we are not talking much here .... but it will work.

The engine can build up amazing speed, but little torque. Your mobile device could be something taken from Cub Scout pinewood derby kits. Some clever, and very lightweight, almost frictionless, belt drives to spin a small bicycle wheel for a flywheel, and slowly sap off power to creep the vehilcle forward, even as the Stirling spins so quickly.

The power source, would be a small can of project fuel, called Sterno, or some other small heat source. Pack an ice back, on the opposite side, to get all the power you can from the Stirling.

For less than $500, including some cool options for the Pinewood Derby car, you have your project. I poke fun of the Cub Scout project, but I have built a few with my kids, and the little car built is very carefully constructed to avoid all friction.

Good luck... We'll call this Plan A. Anybody else can suggest a Plan B ?

OK .. I got Plan B.. next guy can do Plan C.


Plan B #

Plan A fails because it is too difficult to attach any mechanical device to the MM-7, without stopping the thing.

So, I take two rare earth magnets, from the spokes of my bike, and attach them to the wheel of the MM-7, carefully, so they are balanced.

This makes the MM-7 have a heavier flywheel effect, meaning it may take more heat and cold to make it work, but that should be OK with the Sterno can and ice. It will spin.

I then attach the 3 watt electric generator that powers the LED light set on the bike, and fix it, with light-weight erector set parts, very close to the magnets, just as would be on the bike.

Disconnect the light assembly, and just use the power from the generator, to power a 3 watt electric motor.

As long as the Stirling can keep spinning the 3 watt magnets, which will only have very minimum magnetic resistance { no debate, it is obvious from just spinning the bike wheel, only a touch of energy is needed to keep it going }, then the 3 watt electric motor can slowly move the Pinewood Derby car, probably shaped like a tractor.

This meas is time is not a factor, and not cost of fuel, in this case, then the "tractor" moves as long as the Sterno burns and ice pack is cold.

It should get there.

Plan C anybody?


P.S. - The bikelight this is real.
http://reelight.com/
It would be the SL150, and I got an extra set of magnets.

I'm not trying to plug things, but maybe somebody will piece these different bits of Green in a new configuration.

Plan "B" is guaranteed to be an expensive experiment as it will destroy the MM-7 which is designed to run on the heat of your hand! Not on a can of sterno.

"yes i need power.. i need this engine to move itself for at leaset 10 meters.."

An LTD Stirling like the MM-7 is NOT compatible with your requirements.

Check out the resources at

Thank you...
And that is coming from the expert.
It would have been a shame to ruin a MM-7.