3D prints aren’t typically known for their heat resistance. However, [Integza] noted that using the right techniques, it was possible to 3D print parts that could handle steam heat without failing. Thus, the natural progression from there was to build a piston-type steam engine.
Resin prints are key here, as the melting point of such parts is much higher than that of those turned out by typical FDM printers. Try this same build using PLA for the hot parts, and you’ll quickly end up with a pile of molten goo.
To make such an engine work, valves are required to allow steam to flow into alternating sides of the piston to let it reciprocate continuously. A simple slide valve is used, allowing steam to flow to one side of the piston and the other alternately, as driven by an arm coming off the flywheel attached to the engine’s output shaft.
Tested on compressed air and steam, the engine ran continuously, chugging away enthusiastically. However, steam performance was compromised by the low pressure output of just 1.5 bar from [Integza]’s pressure cooker. Similarly, the cooker’s steam capacity was low, so the engine ran for just 15 seconds.
However, it suggests that with a better supply of steam, the printed steamer could indeed run for some time. If you’re not into the wetter engines out there, though, consider extruding a Stirling engine instead. Video after the break.
So often, 3D printer owners buy their machines with the promise of freeing themselves from the shackles of commercial manufactured items, and making all sorts of wonderful and useful things to improve their lives. Then they proceed to print a menagerie of good luck cats and toy elephants, that little tugboat, and a host of other pretty but ultimately useless items in garishly colored filament.
Perhaps this is an unfair assessment, but if you have the sneaking feeling that it might just describe you then could we point you at something that while it still has little use is at least interesting to play with. [Gzumwalt]’s single cylinder air engine is as its name suggests, a piston engine that runs on compressed air. You don’t need a shop compressor though, your lungs or an inflated balloon will suffice.
It’s a simple enough design, but it does incorporate two connecting rods, one of which drives a sliding valve. All the files are available for download, and there is a video we’ve placed below the break showing it chugging away nicely from a balloon. It might not be the most useful of engines and it may not bring you good luck, but it beats a plastic menagerie in the interest stakes.