A clock with a chain that rotates around the minute shaft. Once every hour a number will be at the top.
It uses a regular quarts motor for wall mounted clocks.
The design is inspired by a clock made by Andreas Dober 1993 for Anthologie Quartett.
Print one sets of numbers, face plate, one drive gear and one ring gear (optional). The chain is made out of 12x12=144 pieces of links so they speak for themselves.
I printed these out on a mendel prusa @ 0.2mm thick with ABS plastic.
The chain links are designed with supports added for the studs in the .stl file. Simply break away the supports and ream/drill out the holes so that they are nice and round. Then the links should, with a little care, snap together. The c-c distance is 10mm.
The clock motor I sourced form my local hardware store and is made for 10 to 12 mm thick face plates.
Cut down the hour shaft and fit the drive gear on the minute shaft. I actually managed to fit a 4x8 ball bearing that supports the minute shaft but I think it should work either way.
The numbers are glued into the 2x2mm hole in a chain link.
Make sure that the chain is free and that the gears are smooth.