Geoff Ball’s

HYDRA 7-CYLINDER RADIAL

The annual Midlands Model Engineering Exhibition throws up interesting models of all types, not least I/C engines. Always something new to see.

In 2013 one of the engine highlights was the Hydra 7-cylinder 49cc radial engine by Geoff Ball. This well finished and purposeful looking engine actually started out being a five cylinder to keep the number of parts required to a minimum. However, five cylinders left some gaps in between which looked like there was too much space in between to achieve the desired objective of producing an engine in the style of the early pushrod radial engines. The answer was to make the extra parts and produce a seven cylinder engine. The result is an engine that looks just the part.