Mamiya 645 film transport problem

[ntenny]

I have a Mamiya 645 body that works in all respects except for two funny things about the film transport:

1) The start point is aligned wrong; the camera thinks it's advanced to the first frame too soon, so I usually lose that frame onto the leader. It's not consistent enough for easy compensation at loading time.

2) At the end of the roll, it doesn't behave properly. Instead of winding on freely, it continues to advance and cock for as long as I keep going, as if the film were still in there triggering the feeler. Similarly, I can wind and dry-fire it with no film, which shouldn't be possible.

My guess is that these two symptoms are from a common problem, likely having to do with the film feeler mechanism. I've already bought a replacement body, which was cheaper than any repair was likely to be, so now I'm considering going into the non-working body to see if I can tell what's wrong. I don't have much to lose, as otherwise it's just a paperweight. Does anyone have any advice, experience of a similar problem, cautionary tales, &c.?

Thanks

-NT

 

[Chris Douglas]

If you are talking about the old manual 645, I had some trouble that may be related. When the back is opened, a spring is supposed to reset the counter, but my camera was not reliably doing this so the counter would not show the correct frame number. I just put a tiny drop of oil on the gear shaft that is visible when the back is open, and it completely fixed the problem. I like to use Mobile 1 for lubricating cameras and clocks, but quality gun oil would do as well...no WD40 please! Good luck.

 

[ntenny]

Thanks for the pointer. It is the original manual 645---I'll take a look in there, and I've got a couple of gun-nut friends who undoubtedly can provide some oil.

-NT

 

[mr rusty]

If it continues to wind/cock have you by any chance got a 220 insert in that you are trying to use for 120 film? You can convert 220 inserts to 120

https://www.flickr.com/groups/mamiya645/discuss/72157630005151644/

Not sure about the starting frame though because I thought the leaders were the same length??

 

[ntenny]

Definitely a 120 insert. Fair question though. It never occurred to me to check with a roll of 220 and see if the problem occurs there too.

However, now that you mention it, my 220 insert has always been a VERY tight fit in this camera, and I wonder if something has gotten wedged that makes it *think* there's a 220 insert in. That's another thing I should poke around with.

-NT

 

[Soeren]

IIRC Michael Raso addresses the problem (or at least part of it) in his video on the Mamiya 645
http://www.youtube.com/watch?v=l6gH6DjzdQI

Best regards

 

[Fotocat2]

One other thought

All of the above solutions should clear your problem up, but FWIW i got around the problem by, before sticking in the film insert, reaching over to the right side of the film chamber and gently tuning the little gear until the film counter returns to the "S" (start) indication. The film's paper-back loading mark, the accurate spacing of images, and the "release" of the film for winding off after the last (15th) exposure then work normally for me.