Single Cylinder Air Engine Smaller Edition is the smaller sibling of my previous Single Cylinder Air Engine here: https://www.instructables.com/id/Single-Cylinder-.... While Single Cylinder Air Engine Smaller Edition was designed as a test platform for another design, the test video I posted on Youtube caused a few people to message me to ask for the model, so here it is. I've included a video that shows this engine in a new design I have yet to complete.
Having a smaller total displacement than my previous design, this engine runs longer on balloon power but as a trade off delivers less torque. Also, being smaller and having a crank shaft that is assembled in place requires even more fine scraping, sanding and/or filing and meticulous assembly steps to make this engine work at its peak efficiency, so be patient during the printing, preparing and assembly process.
I probably forgot a file or two or something, so if you have any questions, please feel free to ask.
Designed using Autodesk Fusion 360, sliced using Cura 2.3.1, and printed in PLA on an Ultimaker 3 Extended.
I printed my parts on an Ultimaker 2+ Extended and an Ultimaker 3 Extended using .1mm vertical resolution and 100% infill.
Print two each of "Journal Crankshaft 4mm.stl" and two each of "Journal Crankshaft 10mm.stl". Print one each of the remaining parts.
"Base.stl" must be printed using supports. "Cylinder.stl" must not be printed with supports.
Prior to assembly, test fit and trim, file, sand, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on the colors you chose and your printer settings, more or less trimming, filing and/or sanding may be required. Carefully file all edges that contacted the build plate to make absolutely sure that all build plate "ooze" is removed and that all edges are smooth. I used a flat jewelers file and plenty of patience to perform this step.
Study "Assembly.stl" carefully noting the locations and positions of the various components as assembly proceeds.