The main arbor is made from a brass rod, and is supported on two brass thrust bearings. I cut these from 1/4" brass rod on the lathe. I first beveled the end with a wide drill bit, and then center drilled to a depth of 1/8" with a 5/64" bit.
I pushed these into slightly undersized holes in the frame, so that they are flush with the surface.
Once these were installed, I cut a pivot into one end of the arbor. The end of the pivot is 1/8" long and 1/16" diameter -- giving a little clearance in the bearing. I did most of the work using the slide rest, and then finished it using a hand graver. I checked the polish under 2.5x magnification to make sure it was reasonably smooth and the end rounded.
Once this was made, I cut to rod to length, and cut a matching pivot on the other side. This fits into the frame and allows the arbor to turn freely.
Again using the lathe, I cut a take-up spool for the cord and center drilled it to fit the arbor. A 1/4" drill bit seemed to work, giving a snug fit to the arbor.
The escapement has a rotating arm. I cut this from 1/4" brass rod, and drilled two 1/8" holes at right angles to the axis. I then turned the arbor to a diameter of 1/8" for an inch or so to receive the arm. This wasn't a tight fit, so I soldered it in place.
After this was completed, I added the rods to catch the pendulum as it passes. I didn't really have any systematic way to do this, and it ended up looking OK.
However, it didn't work well. For one, it seems to work best when driven by a very light weight -- about 0.5 oz. Additionally, the spool seemed too big. I also moved the rods around, so that it looked a little different.
Even still, it's extremely temperamental and difficult to get to run smoothly... But here's the best run.
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