Mamiya 645 1000S: Film Counter, Light Seals and Calibration
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
Servicing a Mamiya 645 1000s. This particular example is unusual in that it shows very little wear/use. These were professional tools in the day and often had regular/constant use and some of the ones that I see have reached what I consider the end of their service life. I don’t patch up cameras - if I feel that it can’t be brought back to factory specs without lots of work and replacement parts then I do return the camera with a note saying that it is not economically feasible to repair.
The majority of the 645 models that come into my shop have two complaints: sticking/slow film counter and light seals. Of course, calibration of the shutter is usually also needed but that might not be so obvious to the user.
Replacing light seals is not difficult but is time consuming to scrape out all the residue of the old seals and install new. Good lighting is important with this task.
Photo three shows the camera with the side cover removed. The film counter in the upper left and visible in the upper right is the cylindrical moving coil (solenoid) that releases the second curtain.
Photo four shows the film counter removed from its bearing. The brass bearing assembly is visible to the right of the film counter that I am holding. This bearing needs cleaning as does the counter wheel.
Photo five shows the bottom of the counter wheel and also visible is grease residue. This grease is what causes the counter to return slowly or not at all. If it does not fully return then the film winding does not operate properly and you do not get a full roll of film exposed.
