Hello friends,
My flu is still very bad, so I had a chance to see what I can do about the inoperative distance scale shutter on my Mamiya C330f. It’s easy to remove a side cover, so when I took it apart I saw a puzzling combination of levers, all misplaced perhaps by a previous repairman. The aluminium shutter was firmly kept in place by a piece of wooden matchstick. I had to figure out how the whole system works, and that wasn’t too easy – as I have expected, the scene was missing something important. The scale shutter unit seems to be of exceptionally bad mechanical design – I even thought that some guys from Krasnogorsk or Arsenal should have sneaked in Mamiya constructors’ office and changed something in their blueprints The shutter is spring-closed, there is an another long lever on the cover, also spring-loaded, that transfers a movement from an another lever that senses a small chromed screw on the rack. This latter lever should theoretically have a small steel pole on it, against which an adjustable screw of lever 2 presses. This adjustment screw is needed to adjust an infinity position, and can be found under a small black plastic cover. The problem with my camera was simple – thanks to ingenious design, the pole was broken off the lever, so it became disconnected. I didn’t find it inside the camera, maybe it was thrown away. I tried to make it from good copper wire, but with no success – the load on it is so high that it was bent off from its place after 10-15 focusing movements back and forth. I think the only way to cure it is to make a steel pole again, but with no warranty that it won’t be broken soon like an original one. I did find some information about numerous problems with distance scale among C330 users. Maybe the main source of troubles is a weak pole that breaks off the lever? Judging from the lever shoulder ratios and springs employed, it SHOULD break sooner or later. I will try to fix it from the pure interest, but I seriously doubt that I would ever use the distance scale. So my advice is: if your C330 does not open a shutter on a scale, weep not – it seems to be a serious headache to fix, and not much gain. Interesting enough, how many other fragile poles have been put in C330 by its constructors, eh? Fortunately in left side compartment of C330 is no big gears whose tooth could be damaged by a broken piece of steel.

Cheers,
Zhenya