Some folks just can’t leave well enough alone, and that often ends up being a good thing. Such is the case with this 3D-printed compressed air engine, which just keeps getting better. The design has ...

3D printing is a powerful tool for creating all kinds of stuff, but it has its limits. Hobbyist-focused machines that dispense melted plastic through a nozzle can only make parts that are so strong.

Air engines are a common occurrence here on Hackaday. They’re relatively novel and reasonably easy to 3D print without requiring any fluids or supporting machinery. For example, [Tom Stanton] took a ...