Model Aircraft Styled Air Engine, Experimental

myminifactory

The first model aircraft compressed air powered engine in my series, "Model Aircraft Styled Air Engine, Experimental," was born out of another challenge: to design a single cylinder compressed air engine using just eight 3D printed parts, with no purchased components required. This engine tips the scales at an astonishing .8 ounces (25 grams), incorporating a rotary valve that makes it truly unique. I drew inspiration from Joseph S. Ott's groundbreaking work in 1933, which utilized the propeller axle as both an axle and a valve. The valve timing is determined by the angular offset between the flat surfaces on the axle and the pin on the journal. This clever design also boasts a decent exhaust system. Through the process of designing this engine, I gained valuable knowledge that has benefited my subsequent model aircraft engine designs. While this early prototype may not propel an aircraft, it's a fascinating conversation piece in my workshop, pushing the limits of what 3D printers can achieve. To operate this model, you'll need a 1/4" threaded compressor adapter and a compressor. If you prefer not to 3D print the propeller, a 6 by 5.5 E propeller with a 6.2mm center hole will suffice. As is often the case, I might have overlooked a file or two in the process of designing this engine. If you have any questions or concerns, please don't hesitate to ask – I'm always happy to clarify any mistakes that may have slipped through the cracks. Designed using Autodesk Fusion 360 and sliced with Cura 3.0.4, this model was printed in PLA and PVA on an Ultimaker 2+ Extended and an Ultimaker 3 Extended.