Marble Clock "Time Rolls On"

This is a “simple” 3d printed ball clock that uses 3/8” diameter steel bearings to count the time. (I put “simple” in quotes because designing this thing and perfecting it has been anything but simple.)

My goal was to create a ball clock that could be 3d printed relatively easily on an Ender 3 class 3d printer and assembled without too much fuss. I’ve seen and taken inspiration from other ball clocks (particularly 3Dadicto’s clock: https://www.thingiverse.com/thing:4786491) but they all seemed larger and more complex than what I was going for. This version has only a handful of models that need to be printed (all without supports) and the final assembly is pretty easy.

Additional materials needed:
* 30x 3/8” ball bearings (at minimum)
* 10 M3x6 screws (or longer)
* 1x M2.5 set screw
* 1x Arduino Nano (or equivalent)
* 1x DRV8825 stepper motor (or equivalent)
* 1x Nema 8 (20x20x38mm) stepper motor (the shorter one lacks the necessary torque)
* 1x 5.5mm x 2.1mm DC power sup