Mamiya 7II: Two Bodies Unrepairable from Impact and Water Damage
Originally posted on Instagram. Notes from the repair bench, kept here as a searchable archive. View the original on Instagram
Some of the cameras coming into the shop are not repaired due to major trauma that may not be economical or possible to repair. These are usually impact or water damaged cameras. These two recent Mamiya 7II bodies are an example.
Both of these bodies don’t immediately show signs of a major issue although the one on the left has some scuffs marks and a small crack to the top cover. The back door would not easily open and after getting it open I notice that the body casting has been damaged as shown in photo two. The next step in cases like this is to check the front standard/lens mount for flatness . This camera failed that test showing a deviation of the flange back between (-0.06 to -0.18mm) taking from five points on the lens mount (maximum deviation is (-0.04mm). This test uses the parts show in photo three. Photo four shows the 81.35mm block gauge installed on the camera support and the dial gauge put to zero. Then, the block gauge is removed and the camera is installed on the support with the mount flatness gauge installed in the lens mount. If the mount is flat and distance correct (57.35mm), the gauge should read zero. This camera also had rangefinder issues, curtain problems and a damaged lens helical. It was not repaired.
The camera on the right was also not repaired due to water damage. Initially, the only clue was some corrosion seen in the viewfinder window as in photo eight. After removing the bottom cover, I could see deep rust on many parts which sealed the fate of this camera (also, the rangefinder was inoperative)
I have written about this before and not related to the problems with the bodies, one of the lenses had a 58mm Tiffen UV Protector filter installed. It was a quite terrible filter in several ways and photo nine shows the image it produced on the collimator. The final photo shows what image a good quality filter produces.
