What started as a physics simulation in javascript is slowly turning into a desktop clock.

The latest version runs for a little over a minute before the weight lands on the desk, dropping 4.7 inches per minute as it unwinds from the 1.5 inch diameter spool attached to the 36 tooth seconds gear. The 36 tooth gear drives a 6 tooth gear attached to a 10 tooth escape wheel that is regulated by a deadbeat anchor attached to a pendulum with a period of 1 second.

I measured the accuracy by writing some python code to analyze the audio track of a video recording and detect the ticks as the anchor pallets strike the escape wheel. After some fine adjustment to the length of the pendulum, I have it oscillating at 1.00133 Hz, gaining just 1.33 ms per second or 80 ms per minute. I'm pretty happy with that!