The clock features a series of 3d-printed gears, all driven by a single stepper motor that [ekaggrat] found in surplus. The clock’s controller is based around an ATtiny2313 programmed with the ...

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