Engines come in all varieties and model engines are no exception. Some model engine builders are willing to take on bigger challenges when choosing a prototype to model and Clen Tomlinson went all out with this 18 cylinder 2 stroke engine.
You have to look closely to see what this engine really is. The engine consists of three banks of six cylinders connected together in a triangular configuration. Each cylinder has two opposed pistons connected to a crankshaft at either end. That means three crankshafts and 36 pistons! The full size prototype was a diesel but this model was built as a spark ignition engine. Because it's a two stroke, the intake and exhaust ports are in the cylinder walls and opened and closed by the pistons as they pass by.
The engine is supercharged by a blower mounted at the rear of the engine and driven at six times crankshaft rpm.
Clen Tomlinson, at the time of the article, was 71 years old and was an electro mechanical engineer who worked with paper and pencil and sliderules but taught himself to use AutoCAD 2000 and also to use CNC machinery to help produce this little marvel. It's not quite done but looks absolutely stunning. He lives in England but is a member of BAEM, the Bay Area Engine Modelers club of San Francisco, CA.
It's amazing what these guys do and Clen has raised the bar for what's possible. Very, very nice.
Link: Clen Tomlinson
I’m curious as to how the power from the three individual crankshafts is transmitted to a central output shaft (chain?).