To align holes for each arbor, I made use of the markings for each wheel I had previously made on the middle plate. I carefully drilled through the middle plate with a 1/16" bit. To mark the positions of the anchor hole on the back plate, I aligned the middle and back plates and then drilled through the anchor hole on the middle plate to score the back plate. I did the same (but drilled through the back of the middle plate) to mark the locations for holes of the front plate.
I cut 9 pivot seats (thrust bearings). These bearings are cut from 1/4" brass rod and have a countersunk beveled hole and a small center hole drilled with a 3/32" drill to an additional depth of 1/8". The total length of each pivot is 1/4". (This process takes about 7-10 minutes per bearing.) After drilling and cutting, smoothed the interior surfaces of each pivot with a hand graver and then inspected the surfaces for smoothness at 5x magnification. I didn't polish the bearings, though perhaps this might prove necessary.
To attach a bearing, I first center drilled each location with a 1/16" drill, and then used a 15/64" brad point bit to cut the hole for the bearing. (See below)
I then hammered the bearing (supported by a wooden rod) into its hole.
Once the third, fourth, and escape wheel bearings were set, I tested the fit...
I don't yet have the center or pendulum arbor, so this is as far as the assembly can proceed at the moment. However, there is very little friction. Blowing on the escape wheel is enough to set the mechanism into motion.
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