RB67 180mm Early Lens (1974): Slow Shutter Release
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
This early version of a Mamiya RB67 180mm lens (1974) is being repaired for the typical slow/delayed shutter release. These need disassembly and removal of shutter cocking/release parts, cleaning of old lubrication and installing new Moly Lube compound on the appropriate parts. A very small amount of lubrication is used and if you look at a shutter and see a lot of lubrication, you possibly are looking at an over lubrication issue.
I made a somewhat silly measurement while doing this repair. The amount of lubrication that I use for an RB shutter is approximately 0.034 grams. The jar of Moly Lube that is shown in the photo holds 227 grams. So this container should be able to do 6,676 shutters. While I have serviced a lot of these RB shutters, I have not done over 6000 of them. Maybe that’s why the jar still has plenty of material left inside.
The last photo shows the final step of checking focus on the lens.
