Two Cylinder Wobbler Engine

thingiverse

A compact, two-cylinder wobbler engine. It operates smoothly on compressed air and may even run on steam with the correct filament. Non-printed parts: 2 x 608 bearings 1 x 30mm section of 8mm rod (McMaster:8920k26) 1 x Barbed tube fitting, 10-32UNF thread (McMaster:546K53) 1 x 1/4-20 threaded rod, 4" (McMaster:98752A515) 2 x Compression springs, large enough to fit over rod, about 0.5" long (McMaster:943k72) 2 x unthreaded spacers for M3 screw, 5mm (McMaster94669A099) 2 x M3x20mm pan head screws 3 x M3 set screws When building, position the two crank wheels 180° apart from each other. The pistons are designed to be undersized, ensuring they and the cylinders require minimal cleanup. I've included the Fusion 360 source file for easy modification. Increased stroke length can be achieved by increasing the crank diameter and extending the cylinder as necessary.