This is the most difficult step in reassembly of the shutter in any Leica derived focal plane shutter system. Shown are two pictures from my Leica II ca. '32 project.
Mating the coupling pin [above - 1] to the curtain drum hole [2 - below] as well as shooting the roller pins [1 - below] to the corresponding holes [2- above] of the top superstructure is a task that requires a lot of patience and time.
Aside from that, the orientation of the curtain drum assembly relative to coupling with the release gear [3] underneath in the wound position has to be right on or else the shutter will not work properly [this picture approximates the proper orientation and the shutter worked].
All of these have to be done in one shot!
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