I used the reference mark on the front of the front plate to determine the center line of the front plate. I clamped the regulator block to the top of the front plate on the center line with a drop of Super Glue, then I used the existing holes in the regulator block as guides to drill two holes for mounting screws in the clock plate. These holes are the size used for 2-56 threads. Once the holes are drilled, tbe Super Glue "clamp" can be broken with heat, and the glue residue removed with acetone.
After that, I tapped the two holes in the regulator block for 2-56 screws and enlarged the two holes in the clock plate for the outside diameter of 2-56 screws. I used flat-head screws, using a reamer to make conical seats in the front of the plate for the screw heads. This makes it impossible for the regulator block to shift.
I also made a "collet" for the balance spring from 1/8" brass. It has a cross hole drilled and threaded for the two gnat-like 0-80 set screws that clamp the upper end of the suspension spring. It also has a .014" longitudinal hole for the suspension spring. After the holes are drilled, one end of the collet is reduced to 3/32", so it can fit in the hole in the suspension block. The collet is secured in the suspension block by a 0-80 set screw, the hole for which was made earlier when the block was made.
I also found a spring. It fits over the 3/32" regulator foot shaft, and will provide downward pressure to the foot during adjustment. When I thread the regulator shaft, I'll trim the spring to the proper length.
The suspension spring is .0025" thick, and the balance wheel rotates with a nominal rotation of 4 RPM with the regulator set at an average position, as timed by a stopwatch. If needed, the spring can later be changed for a spring slightly thicker or thinner. Right now, it's enought that it's all in working condition, and approximately on time.
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