Also for $29.99 is the Exploring Kid Steam Engine Kit. This mostly plastic kit, when assembled, includes a boiler and tube leading to a piston. Due to the open flame and numerous small parts ...

However, [Attila Blade]’s version of a free-piston type Stirling engine is simple enough to be built in a matter of minutes. To build the engine you only need a test tube, steel wool ...

We all know how a conventional internal combustion engine works, with a piston and a crankshaft. But that’s by no means the only way to make an engine, and one of the slightly more unusual ...