With a size of 8 x 8 x 5.5 mm and a 0.2 mm step size, this motor is the smallest 3-D printable pneumatic stepper motor. The cylinder cross-section is only 2.5 mm square. Print a few spare pistons, if you drop one on the floor then you may not be able to find it back.

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It is essential to print it in the highest possible resolution, in order to make the triangular teeth as sharp as possible. If you get sine-wave shaped teeth instead then it may not work.

Cut seals sized 2.6 x 2.6 mm from 0.5 mm silicone rubber. Experiment with best settings until you get a good tradeoff (low friction and low leakage).

When printing with a Polyjet printer (e.g. Objet260 Connex3), use glossy print mode to make cylinder walls as smooth as possible.