Mamiya 645 Super: Shutter Service and Mirror Stop Replacement
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
Shutter service and mirror stop replacement on Mamiya 645 Super. This camera came into the shop with the shutter locked open and a broken mirror stop. It seems like most of the Mamiya Super and Pro bodies these days have a broken mirror stop as the plastic stop cracks after so many years. And we are now at so many years. If the broken stop is not noticed right away, part of it and/or the spring can come loose and get stuck in the shutter causing a more extensive repair.
After fixing the mirror stop and adjusting mirror angle, next step is to check and adjust shutter curtain travel times and shutter speeds. In the third photo, you can see the travel times and they are off by a bit which will cause incorrect shutter speeds or tapering of the shutter. Correct travel time is 13.5ms +-.2ms. As you can see in the last photo, this camera was adjustable to specs.
