Otokichi 9 Report post Posted May 28, 2018 "Techmoan" is back with a pricey "heat difference" engine kit. This up-and-down-piston-action engine operates via the difference in temperature between one surface and the other. It even works under bright sunlight! If the conditions are right, setting it in the palm of your (warm/hot) hand will start a "mechanical magic" show.;) Share this post Link to post Share on other sites
