This is an easy to build 3D printed clock that has runtimes of up to 32 days. The initial design goal was to simplify the bill of materials to make it easy to acquire the non-printed parts. These changes made the clock very efficient and it has 32 days of runtime using only 5kg of weight. Options for shorter runtimes would need much less weight. The first design shown is available at The large version of the clock seen in the second half of the video is available at The larger gear size take more energy so the runtime is limited to 21.5 days. Assembly videos for both clocks should be available soon. The complete bill of materials to build either clock is: PLA for small clock, PLA for large clock 25 6x3/4" wood screws 18" 3mm metal rod 9" or 1/16" metal rod 12' fishing line 5-10 lb. BBs or lead shot for the weight shell 5 623RS (3x10x4mm) bearings 4 springs from a ball point pen 44 pennies for the pendulum bob Related videos: Assembly part 1, basic components Assembly part 2, final assembly Debug steps Steve