RB67 Lens: Fitting a Newer Shutter with External Sync Terminal
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
Mamiya RB67 lens replacement of shutter. I am getting ready to replace an old style RB shutter (circa 1972) with a newer designed shutter. The new shutters don’t quite drop in place, there are a few modifications to be made to the lens, the most obvious is that the new shutters have an external sync terminal. The original shutters had a sync terminal that was part of the shutter housing (photo two shows the old style shutter on the left, sync terminal at six o’clock position on shutter housing). The task is to install a new sync terminal on the old shutter and this requires drilling two flash base installation holes and enlarging the existing sync terminal opening. The first photo shows a fixture and jig that I use to mark the holes for drilling and tapping (1.7mm threaded holes)
Photo three shows the two different styles of old shutter sync terminals (built into the shutter) and photo four shows the newer style.
This is a job that I did quite often when these lenses were used professionally and were quite costly to replace.
