Ivan Miranda loves to make stuff using his 3D printer. So he decided to build a marble clock. But he realised he made a big mistake so while there are two parts (above) he has promised a Part 3 to make the build work.
It works like this: black and white marbles go into the elevator at random, some colour-detecting sensors and the “wrong” ones get ejected until the right one are funnelled into position to display the correct time. And so it repeats. The issue arose with the colour detection but I’ll leave Ivan to explain that so go watch the videos.
(via Hackaday)