https://www.woodenclocks.co.uk/clock-1/
I converted the free pdf linked above into 3D files using inkscape and Fusion 360. For the amount of effort involved it would be sensible to pay the man. What can I say ? I'm cheap and enjoy a challenge. Also I've paid for the clock #22 plans so it's not total freeloading ☺
All gears are birch ply cut with a downcut spiral to reduce tear out. Maple was used for the escape wheel and pawl resulting in smoother sliding surfaces than possible with ply. The frame is oak. The drive weight was a rolling pin in a previous life.
A good running clock doesn't rely on tight tolerances, in fact a bit of slop is necessary. The gears don't need to be tightly meshed because there is no change in the direction of rotation. The shafts need a bit of a loose fit in the frame due to the 'living' nature of wood and frame sag caused by the drive weight. This is one of the reasons why my clock uses no bearings. The only place I did consider bearings is on the shaft supporting the drive weight. One place precision does matter is the bore of the escapement wheel, this bore must be as close to centre as possible. A off centre or out-of-round escapement wheel will not provide a regular tick-tock beat and may not run at all.
Friction is the enemy. Clocks are gear-up drive trains where wheels (the larger gear in a pair) drive pinions (the smaller gear). Following the gear train from the large wheel at the weight pulley to the escapement wheel speed is gained through each succession of gear pairings. This increase in speed comes at the expense of torque. My clock powered by a 5 lb weight can be stopped by a feather at the escapement wheel ... literally. Friction must be reduced where ever possible and this is especially true for the top shaft where minimal torque is available. The shaft are highly polished where free rotation is needed and the non-fixed bores are lubricated by wax crayon shavings. Gear teeth are sanded smooth.
My clock is slightly different than the original design. The shaft sleeves were not used. The gears are either interference fit to the shaft or free rotating. I'll leave the reader to figure out which fit was used on any particular gear. The pinion on the lowest shaft has been pinned in place. Two threaded rods tie the frame together rather than the fussy pins+pegs seen on the original. One weak part of the original design is the pawl on the winding ratchet. This pawl needs to be heavier in cross-section or completely redesigned. It's holding power is marginal at best and if it slips the drive weight will crash to the floor.
Links of possible interest:
a good explanation of clockworks
https://www.finewoodworking.com/2009/01/07/designing-wooden-clockworks
Lots of general information
http://garysclocks.sawdustcorner.com/
A wealth of information if you dig deep enough
https://lisaboyer.com/Claytonsite/Claytonsite1.htm
Forgot to mention my clock runs 9 hrs before the weight touches the floor. Accuracy is reasonable but for time keeping
I recommend something from Walmart.
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