RB67 Lens Repair/CLA agent recommendations

My Mamiya RB67 360mm lens (non-C, Seiko shutter) has started firing intermittently on my RB67 Pro-S. Consequently, I lost several images (basically from image 4 onward) on the last two rolls of 120 shot. The film is clear on the later frames, indicating no-exposure at all.

I have tested several of my other RB67 lenses on this body, and they all fire 100% of the time, yet this 360mm lens fires once or twice, and then not at all. It is due for a CLA.

Therefore, can anyone recommend a repair/tech shop in Canada (my base) or the USA that will perform work on this type of lens? Thanks in advance.

PS> I checked the fine print of KEH Repair Service and it explicitly states they will not accept international repairs because of customs hassles (so much for NAFTA making things "easier"). Too bad.

It sounds like the shutter may have a spring issue. Try firing it off camera to see exactly what it's doing? If you cna describe the symptoms in terms of operation sequance, it may tell me a bit more about what's going on.

So when you fire it and start turning the pins, does it close down, then fires... or just never opens... or never fires after closing down? Are the shutter blades oily?... the iris oily?... any leafs seem out of place?

Is there any play in the barrel? ...does it seem loose?

When firing the shutter, does the roatation seem gritty or smooth?

Paul, NYC
automax1@juno.com

As I mentioned in another recent post, give Paul Ebel in Wisconsin a try. The number I have for him is 651-335-8759. I don't have an email address for him.

I have sent a few lenses back to Mamiya for services--they have done a great job!!!

paul ron said:

It sounds like the shutter may have a spring issue. Try firing it off camera to see exactly what it's doing? If you cna describe the symptoms in terms of operation sequance, it may tell me a bit more about what's going on.

Click to expand...

Hi Paul, as I wrote earlier, mounted on the camera, the shutter fires once after being cocked and mounted, and maybe twice, but often the 3rd or following shots, the shutter does not fire.

paul ron said:

So when you fire it and start turning the pins, does it close down, then fires... or just never opens... or never fires after closing down? Are the shutter blades oily?... the iris oily?... any leafs seem out of place?

Click to expand...

When I demount the lens, and then uncock the shutter, it does the following:
[1] the aperature leaves close
[2] then, as the pins near the end of their travel to the uncocked position, the shutter fires consistently.
[3] it just does not fire consistently when on the RB67 Pro S (after the 1st shot after mounting).

paul ron said:

Is there any play in the barrel? ...does it seem loose?

Click to expand...

No play at all in the barrel.

paul ron said:

When firing the shutter, does the roatation seem gritty or smooth?
Paul, NYC
automax1@juno.com

Click to expand...

The rotation is smooth - no sense of grit at all.

Any thoughts you have about this situation are much appreciated. Have a great Easter!

There are 2 places in Winnipeg that I've used, and both have done great work for me.

1. Computech Cameras
2. Precision Cameras

Both are on Sherbrook St. You can find the numbers via Canada 411. Both will do a free estimate, and both guarantee their work for at least 6 months (Computech might be 1 year).

John

OK it seems from your posts it is only this lens that does this, not your other lenses, that eliminates the body. So.....

It can be a few things happening... it can be the MLU lever hanging it up but that would happen off camera as well. It can be the pins that register with the body mount are worn or out of alignment, slipping out of the body holes or not cocking properly (rotation is too short, not locking the shutter)... OR perhaps the locking ring is not tightening down the lens far enough. You say there is no wiggle in the lens barrel, no wiggle in the mount when it's on the body?

The lens just doesn't fire or do anything at all when it misses, anything happening when it misses? When you remove the lens after a missfire, do the pins sort of "snap" out of the holes?

Cock the lens on the body while watching the front of the lens till it missfires to see if it actually cocks before missfires, watch from inside the camera with the back off to see exactly what's going on as well?

How handy are you? Are you considering doing your own repair or want to send it out?

e-mail me, we can talk off line alot faster that way? I only drop by here only a couple times a week but do my mail everyday.

Thanks to all for your comments and repair suggestions. My problem has gotten a bit bigger as I have the same problem with my 180mm as well as my 360mm on my RB67 body. Yet, only these 2 lenses of the 8 RB67 lenses I own have this issue - all others work fine. Then, to further complicate things, the 180 and 360 work just fine on my RZ67 body. I am starting to get suspicious that my problem may lie with the RB67 body itself and its inability to cock the 180 and 360 lenses on subsequent cycles after mounting. Hmmmm....

Just like driving a Ferrari--it's carbon on the valves.
But in real life it's possible that the cocking rack on the lens is either not traveling far enough to cock the lens or & I've only seen this one once. There could be a worn spot on the cocking lever..It could be either body or lens. Look for a small groove on the mating surfaces. Depending on where it's at (body?) It may be less expensive to replace than repair.