First, let me say that I thoroughly enjoyed building your SP4 Easy Build Clock. The design is excellent and the clock is running well and looks great! I built the 10-day version, it's running with only 4 1/2 lbs of weight, and it's accurate to within 1 min. per week
FYI, I did have trouble with Gear 9, the inserts, and the S9 spacer. No matter how hard I pushed and hammered the inserts would not press into gear 9. I ended up designing a copy of the inserts using measurements from Gear 9 and got that to press in. Then, the hole in gear 9 for the arbor was not deep enough by at least .25 in. I drilled that out and then discovered that S9 was too long by about .08 in. I reprinted it shrinking the Z-axis. I have checked my printer's dimensional accuracy and it's surprisingly good. Plus all of the other parts worked fine as designed. All is well now and I'm not meaning to complain, but if I was you, I'd want to know.
I'm very happy with my clock. In fact, so much so, that I may build one of your desk clocks when I get time. :)
Thanks for the feedback. The easy-build clock series was designed around comments like yours.
Many parts are a compromise between too loose, too tight, too big, or not strong enough. The inserts were originally printed in place with gear 9, but they snapped on the layer lines. Laying them flat makes them much stronger. There are always other solutions. Maybe a simple square insert would be easier since it could easily be scaled to make it fit across various printer tolerances.
I am doing an update to the stepper motor desk clock right now. It is quieter and it uses easier to find parts. See New Stepper Motor Driver | Steve's Clocks (stevesclocks.com) for a preview of the electronics. It should release in early January. Anyone with the old design will get the upgrade. And the new electronics make a larger version quiet enough to release.