The animation explains how works this engine better than any speech.
The crank-shaft is original of an old sewing-machine.
You must add an eccentric 90° out of phase which drives the little brass-piston for steam entrance and exit (slide valve).
The fly-wheel is original of the sewing-machine.
The steam pressure is about 3-4 kg/cm².

Our engine mpeg videoclip (1,5 MB)