Thanks for the great design. Was a lot of fun to build. Not quite enough oomph to keep the 10 days gears running consistently, even after polishing all gears and making sure pendulum engaged at correct angle (suspect one or more gears slightly out of tolerance). Found solid wall mounting was required to not slow pendulum swing. Setup with 7 day gears, works great. Used Inland Tought PLA for entire clock. Hoping that this allows for a longer life span and better wear on the gears. Used hybrid bearings with ceramic bearings in metal housing. Pendulum will free swing between 18-20 minutes. Been running for about a week. Have been narrowing in on correct time with pendulum adjustment (speeding up and slowing down). Only adjustment to build was to shrink z height 1mm for spacers 4a, 1, and 2. Also needed to reduce arbor length by about 1/8 inch on main arbor, and pendulum. Sons cannot believe it runs without batteries. Sign of the times.