Always wanted one of these engines so I built one from my scrap box(es). The cylinder is an overrun from the foundry I frequent. The flywheels are bronze ~6” gears with tin rims cast onto them. The piston is a cast iron sleeve with a top silver soldered on. The intake valve is a piece of 12 mil shim stock with a 3/8 hole in it sliding in a 14 mil slot. The stack is a ball check to allow any pressure within the cylinder to be relieved and IMO, makes for an easier to run engine. I’ll show the finished product here and then show some of the build photos.