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 ...

There are only a couple of important parts between the engine and the boiler. There’s an in-line oil reservoir to help combat the corrosive nature of the steam. There is also a check valve.

Before the steam engine can be called an economical power ... A large quantity of heat is lost by radiation from all parts of the boiler. It is true we felt the exposed surface, but this is ...

It all worked in the end, enough so that the engine managed 42,000 RPM on a test with compressed air. We eagerly await the equally tiny boiler for a live steam test.