[shiura]’s Hollow Clock 3 is a fantastic 3D printed take on ... A concealed shaft and gear assembly takes care of that. For every full rotation of the minute hand (actually the white ring ...

[Uri Tuchman] had a different idea. He wanted to make a clock out of the gears used in the lathe. Can he do it? Of course, as you can see in the video below. Along the way, he used several tools.