Five Cylinder Rotary Engine Plans

This is a tiny five cylinder rotary engine designed to run on compressed air/steam/CO2. This engine runs fabulously on around 10psi of compressed air and happily swings an 8.5 inch propeller.

  • 9mm bore
  • 9mm stroke
  • 85mm overall engine diameter

five cylinder rotary engine plansThis engine can be made using a small 3.5″ centre lathe and a small milling machine. You will need a rotary table in order to be able to machine the crankcase and the master conrod. This is a challenging engine to make, but easily within the reach of a model engineer who has previously made a single cylinder steam engine. The original design and build of this engine is featured in Five Cylinder Rotary.

The elegance of the master and slave connecting rods comes alive when making and then running this engine. The engine can run with the crankcase cover / propeller mount removed, thus allowing you to observe the rotation of the master conrod with the cylinders. The crankshaft is stationary with the crank pin also being fixed.

Even after 10 years I still quite often run this engine on compressed air as it just entertains everybody who sees it.

The pdf download is a 15 page document of technical drawings, images and lots of notes on the engine design.

Remember: the download link is on the payment confirmation page. However, if you have any issues then email me: