RB67 Pro S issue

[Michael Leuck]

Hello:

I am having an issue when shooting with my RB. After attaching the lens (shutter cocked)and releasing the shutter, the lens works. After the first shot, I cock the shutter and fire again, but the lens shutter does not open, thus no image.

Any help will be greatly appreciated.

Thank you

Michael

 

[Wayne]

Is the darkslide pulled out past the indent in its edge? Its not clear if you're taking a picture or just testing it, but the darkslide has to be pulled out a certain distance, (among various other things)

 

[Trail Images]

Along with Wayne's point have you tried working and testing the lens and body separately? If nothing obvious the lens could need a CLA. Only time I had lens intermittent issues was do to needing a CLA.

 

[Michael Leuck]

Thank you for your replies. Yes, the dark slide is out and the lens works correctly when off the camera. The problem is.. the shutter lever on the body will not cock the lens shutter after the shutter is released once (after placing it on the camera).

 

[Trail Images]

Not sure if at this point it makes a difference, but do you have the double exposure ProSD back on this unit? Although I think mine will still cock it just will not trip the shutter if the back is not advanced or the DBL exposure lever is not moved.
Not being able to cock after a shutter being triggered is not anything I think I've had. Unless if the lens was not coked originally before being mounted on the camera. Sorry, looks like it will take some more help maybe........
......I wonder if taking the back off during the testing might help isolate the issue.

 

[flavio81]

Please give a more detailed description of the malfunction. Does the mirror rise after hitting the shutter button?

 

[flavio81]

Not being able to cock after a shutter being triggered is not anything I think I've had.

I've had this problem but it was with a RB67 that had been messed with. The arc of rotation of the shutter cocking device within the camera wasn't correct enough. In the manual, if the end position is not correct, it is said it can be corrected by changing the relationship between the shutter cocking device (the one around the lens mount) and the sprocket that drives it (it is hidden below the lens mount).

To do this one needs to remove the front face of the camera (the one that says "Pro-S" around the lens mount), and then the lens mount. It is easy.

In my camera, not only the end position was wrong, but also the arc length (amount of rotation) wasn't long enough and this required major dissasembly.

 

[Skiver101]

I used to have a Pro s and I seem to recall having the same issue.

Try here, page 39. I'm almost sure I found the solution here.
Worth a look... http://www.cameramanuals.org/mamiya_pdf/mamiya_rb67_pro-s.pdf

There are also setting levers at the contact end of the lens that need to be set for mounting. Sorry, it's been a while since I had this camera.

JP

 

[Michael Leuck]

Please give a more detailed description of the malfunction. Does the mirror rise after hitting the shutter button?

The mirror rises after hitting the shutter button. The problem is that the lens shutter has not been re-cocked after its first firing. Therefore, the mirror rises, but the lens does not open.

 

[Theo Sulphate]

Are you winding the film lever also?

Does it have a Pro S back as well?

Is the lens set to mirror-up mode?

Cock the camera with the lever. Then wind the film lever. Unless you're winding the film lever each time (and double-exposure lever is off), then I think you won't be able to release the shutter.

 

[Michael Leuck]

Not sure if at this point it makes a difference, but do you have the double exposure ProSD back on this unit? Although I think mine will still cock it just will not trip the shutter if the back is not advanced or the DBL exposure lever is not moved.
Not being able to cock after a shutter being triggered is not anything I think I've had. Unless if the lens was not coked originally before being mounted on the camera. Sorry, looks like it will take some more help maybe........
......I wonder if taking the back off during the testing might help isolate the issue

I removed the back, but no change. The lens shutter on fires once and then, seems to not re-cock when using the shutter cocking lever.

 

[paul ron]

check to see if the lens is set to mirror up mode?

 

[Trail Images]

After reading all the input I noticed Skiver101's link to the ProS user guide. I might take a review of page 12 & 13 to verify all procedures are being done correctly there. If so, then the page 39 he has pointed out may be a follow up test to see if they correlated to the issue.
I found stripping the camera down at times to the bare body and making sure all tests of cocking & mirror up and down during cocking & release, etc....are past as I added hardware to it can help too.

 

[Michael Leuck]

check to see if the lens is set to mirror up mode?

Not in mirror up mode

 

[Michael Leuck]

Are you winding the film lever also?

Does it have a Pro S back as well?

Is the lens set to mirror-up mode?

Cock the camera with the lever. Then wind the film lever. Unless you're winding the film lever each time (and double-exposure lever is off), then I think you won't be able to release the shutter.

1. I am winding the film lever.
2. Pro S back
3. Not in mirror up mode.
4. When I cock the camera with the lever, the shutter in the lens is not cocked by the lever. When pushing the shutter release button, the camera fires, but the lens does not.

 

[flavio81]

1. I am winding the film lever.
2. Pro S back
3. Not in mirror up mode.
4. When I cock the camera with the lever, the shutter in the lens is not cocked by the lever. When pushing the shutter release button, the camera fires, but the lens does not.

I insist, this must be that the pins on the lens shutter (for cocking) are not twisted through the whole arc. Thus, the shutter does not cock.

As i said, i've experienced exactly the same problem.

But you should try another lens, to see if perhaps the lens is at fault (requires more "travel" than what the camera should give)

 

[Michael Leuck]

I insist, this must be that the pins on the lens shutter (for cocking) are not twisted through the whole arc. Thus, the shutter does not cock.

As i said, i've experienced exactly the same problem.

But you should try another lens, to see if perhaps the lens is at fault (requires more "travel" than what the camera should give)

You are absolutely correct. Sadly, I have tried 4 lenses (50, 65, 90, 140) without any luck.

 

[Trail Images]

Sadly, I have tried 4 lenses (50, 65, 90, 140) without any luck.
If I understand you correctly all lenses have the same issue. Meaning, you hand cock the lenses prior to mounting them. You also cock the camera before mounting the lens. Once the lens is mounted you look through whatever view finder and can see that the shutter is wide open and all is normal for first shot. Then you release camera silver button and the mirror goes up and the shutter cycles through whatever speed its set for and the blades close.
It is only after all this you re-cock the main camera lever and the mirror moves to the open position, but the lens does not reset to an open position.
If all the lenses work off the camera then it sounds like a travel issue on the cocking lever to me at that point. Basically, if the lenses only operate on the camera with the first operation they are doing it off your manual cocking process before mounting them. After that they have to have the cocking lever do the operation.
With the lens removed I might look with a good LED flashlight at the front of the camera to see if the cocking lever is moving the items on the front that actually twist the lens pins. If that area appears to be working then it sounds like some kind of total travel item not twisting the lens pins far enough to open them.

 

[Michael Leuck]

If I understand you correctly all lenses have the same issue. Meaning, you hand cock the lenses prior to mounting them. You also cock the camera before mounting the lens. Once the lens is mounted you look through whatever view finder and can see that the shutter is wide open and all is normal for first shot. Then you release camera silver button and the mirror goes up and the shutter cycles through whatever speed its set for and the blades close.
It is only after all this you re-cock the main camera lever and the mirror moves to the open position, but the lens does not reset to an open position.
If all the lenses work off the camera then it sounds like a travel issue on the cocking lever to me at that point. Basically, if the lenses only operate on the camera with the first operation they are doing it off your manual cocking process before mounting them. After that they have to have the cocking lever do the operation.
With the lens removed I might look with a good LED flashlight at the front of the camera to see if the cocking lever is moving the items on the front that actually twist the lens pins. If that area appears to be working then it sounds like some kind of total travel item not twisting the lens pins far enough to open them.

You understand the problem exactly. I have isolated the issue to the meshing of the gear teeth. To travel completely, the cocking gear must be meshing between the first and second tooth of the gear. My guess is that mine is not, thus the no cocking of the lens shutter. My issue is how to fix this issue. Does anyone have any expereince in this?

 

[Trail Images]

You understand the problem exactly. I have isolated the issue to the meshing of the gear teeth. To travel completely, the cocking gear must be meshing between the first and second tooth of the gear. My guess is that mine is not, thus the no cocking of the lens shutter. My issue is how to fix this issue. Does anyone have any expereince in this?

Ok, at least you have the problem identified. I wish I had a fix idea but I do not. I hope others will come to your aid. Good luck.

 

[Michael Leuck]

Ok, at least you have the problem identified. I wish I had a fix idea but I do not. I hope others will come to your aid. Good luck.

There will be someone out there that will have the info to help. Thank you for your time. I really appreciate it!

Take care

Michael

 

[flavio81]

You understand the problem exactly. I have isolated the issue to the meshing of the gear teeth. To travel completely, the cocking gear must be meshing between the first and second tooth of the gear. My guess is that mine is not, thus the no cocking of the lens shutter. My issue is how to fix this issue. Does anyone have any expereince in this?

I already explained above on how to alter the travel of the camera cocking system:
(there was a url link here which no longer exists)

To change the end (and start) position is very easy.

Try this before further dissasembly.

 

[paul ron]

The reason I asked about the mirror up, the lens will sound like it fired but is waiting for a cable to trip it... no matter how many times you fire the camera, the lens will not recock till the shutter is cleared.

OK so you think its the gears not meshing properly..... it just may be so since all your lenses are having the same problems. Have you always owned this camera or was it a recent purchase?

If excess force were used on the lever at some point because of a locked lens by improper mounting or for whatever reason the lever refused to move due to safety locks and the user tried to over ride them by force....

A gear inside the left compartment of camera probably sheared on its shaft. It can be repaired by installing a pin to keep it in proper alignment on the shaft to mesh in sync and realigning the works since their adjsutments may have changed or bent as well. Its quite common to happen to first time users.

That will definitely give the symptoms you describe.

A repair of this kind can cost anywhere from $100 to $200 depending on if parts need to be replaced. But also consider part of that cost is replacing internal light seals on that side of the camera while in there. Those seals, Ill bet have never been serviced since the Pro that originally owned it had it in for maintenance... 30 years ago?

 

[flavio81]

Besides the advice of Paul Ron, who probably knows 10 times more than me about this machine, what I had was a RB67 pro-S body that was messed with and had the same symptom: camera unable to re-cock the body.

In my case the travel of the shutter cocking circular plate (the "device" that engages with the lens shutter pin) had two problems:
a. the end position was not clockwise enough, so the lens was never cocked
b. the arc (total travel) of the 'device' wasn't long enough, so "a" was not achieved as well.

As mentioned, "a" is corrected by removing the lens mount (and lens mount surrounding fairing) which will reveal the small pinion/sprocket that drives the "device". This pinion is held in position by two screws. If these screws are removed, and the pinion is moved down (by a little bit of force), the position of the "device" can be altered (relative to the pinion) and thus the end position.

For "b", i had to disassemble the camera and in effect, as Paul Ron suggest, there was a bent component inside the side panel that has the cocking lever (the "big" lever on the side of the camera). But this didn't cause the problem; it was just a sign that the camera had been forced by yet another guy that does not read the manual before using this wonderful machine. So what happened is that, somehow, gears had skipped or something, and the total travel of the 'device' was restricted. This was repaired, by me, an amateur, by removing the side panel opposite to the cocking lever. There, the sprockets that translate the movement of the cocking lever to the movement of the 'device' are visible and by removing the main sprocket*, which is opposite the cocking lever, i could realign things so there was a bigger 'arc' of movement at the 'device'. It is obvious once you remove the side panel.

(*) to remove this sprocket (or change its starting position), the plate on top of it needs to be removed, and this will reveal a lot of tiny bearing balls. They need to be removed carefully to be able to remove the sprocket. And need to be put back in position to install the sprocket again. Needless to say, this is a rather time-consuming job.

An observation: the side panel that is opposite to the cocking lever has light seals that need to be replaced or cared for, otherwise there could be light leaks coming from the mirror pivot.

After doing these steps, as well as correcting another minor problem, i could bring that RB67 to life.

 

[Michael Leuck]

To do this one needs to remove the front face of the camera (the one that says "Pro-S" around the lens mount), and then the lens mount. It is easy.

Thank you.I understand you explained the process and I feel this will solve my issue. But, how is the front face removed? Where would I find the screws. Are they under the material which covers the metal? Which side? Both sides?

Thank you for your help.