How to fix small dent in attachment ring for RB67 lens?

[philcameraman]

I just got a 250mm lens for my RB67 Pro, but was frustrated because it seems to not lock onto the camera. I can get it on and line it up with the mouth of the body, but the ring with the red dot on it will hardly budge, so I can't tighten the lens on. The lens does interact with the body fine, shooting when I press the body shutter button, it's just not securely attached. Also, the ring moves fine when the lens is not attached to the body.

I think I've found what the issue is. There's a very small, almost imperceptible dent on the outside of that ring, pushing it inward. I think that dent is making one of the inner parts of the ring catch on part of the body's mouth so it won't turn. I'll include two pictures, the first of which shows a normal outer part of the attachment ring and the second showing the dent to illustrate what I'm talking about.

I'd like to fix this if possible. I tried to see if I could pull it back into place easily with pliers but it hardly seemed to budge and I only scratched the varnish. Is it possible to remove the ring so I could place it on something and safely hammer it back into shape? Or should I just ask for a return from the seller, saying the lens was damaged during shipping. Any advice?

 

[Mamiya_Repair]

The ring can be removed and the dent straightened out (usually) with tools. I use wooden tools, a pliers would not be recommended. Seems to me if you just purchased it a return might be in order though...

 

[philcameraman]

How is the ring removed?

 

[Mamiya_Repair]

Remove the small stop screw on the side of the ring and unscrew the ring from the body.

 

[AgX]

Bulging-out such dent always involves the risk to bulge the adjacent material (rim in this case) too. Thus moving from one issue to another. In this case grinding off the in-bulge seems the more safe approach.
With modern tools this is typically is no problem, but as any such repair needs experience to get it nice.

 

[Sirius Glass]

I tried that using all the right tools ... and I destroyed the lens. Do not cheap out, sent out to get fixed properly OR just save the time and aggravation and time and buy another lens.

 

[philcameraman]

I tried that using all the right tools ... and I destroyed the lens. Do not cheap out, sent out to get fixed properly OR just save the time and aggravation and time and buy another lens.

Do you know how much it should cost for a repair like that?

 

[Sirius Glass]

Do you know how much it should cost for a repair like that?

Uh, that would be "No". Sorry. But cheaper than replacing the lens once you damaged it beyond use.

 

[philcameraman]

The ring can be removed and the dent straightened out (usually) with tools. I use wooden tools, a pliers would not be recommended. Seems to me if you just purchased it a return might be in order though...

I was thinking a better alternative to repair might be to get a for parts lens and use the attachment ring from that. Do you know if the rings from different size lens fit each other or would I have to find a 250mm lens of the same type?

 

[Mamiya_Repair]

You will want to get a lens of the same style and version of what you have. The rings have slightly different form factors.