PDA

View Full Version : Jammed retaining ring



Douglas Henderson
2-Dec-2011, 11:09
This pertains to a 6x6 camera--but perhaps the problem could be shared with bigger lenses. I have a Franka Solida folding camera with an Ennagon 75mm lens (nice glass)--which is not flush with the standard (angles off to the left) because someone (not me-- I just bought it) screwed the retaining ring behind the standard on cockeyed--and it is simply jammed on tight. I've already done some interior finish damage monkeying with it and am considering hauling out a Dremel and grinding through the ring to get it off.

Any other avenues? Anyone know what the diameter of a replacement ring would be (if the threads on the lens aren't ruined as well).

Ari
2-Dec-2011, 11:33
Try unscrewing it with a lens wrench first, don't dremel unless there's no other choice.

http://www.ebay.com/itm/Spanner-Wrench-1-32-Great-Tool-Lens-/360410858466?pt=LH_DefaultDomain_0&hash=item53ea2943e2#ht_500wt_1156

Sirius Glass
2-Dec-2011, 11:36
The wrench Ari mensioned is sold new at http://www.skgrimes.com/products/spanner-wrench in two forms.

Steve

Drew Bedo
2-Dec-2011, 11:36
There are only three sizes of retaining ring really: Too large, Too Small and Wrong Thread!

Ok—If you do not feel confident in resolving this yourself, I would get a repaire technician involved.

I use Mike Hakeem at Professional Camera Repair here in Houston. S. K. Grimes is well thought of by many as well.

Matt Ellison
2-Dec-2011, 11:39
I'm not familair with your particular problem, but the most effective way to help loosen a stuck nut is heat. Try applying some moderate heat directly to the nut; this will make it expand and should make it easier to remove.

Sirius Glass
2-Dec-2011, 11:51
Douglas, where are you located? One of us maybe nearby and can help you.

Please put your location in your profile so that it is displayed with your name.

fenderfour
2-Dec-2011, 12:27
Carefully apply some penetrating oil to the threads. Wait. Apply some more, wait. Try unscrewing it again.

Capocheny
2-Dec-2011, 18:53
This pertains to a 6x6 camera--but perhaps the problem could be shared with bigger lenses. I have a Franka Solida folding camera with an Ennagon 75mm lens (nice glass)--which is not flush with the standard (angles off to the left) because someone (not me-- I just bought it) screwed the retaining ring behind the standard on cockeyed--and it is simply jammed on tight. I've already done some interior finish damage monkeying with it and am considering hauling out a Dremel and grinding through the ring to get it off.

Any other avenues? Anyone know what the diameter of a replacement ring would be (if the threads on the lens aren't ruined as well).

Douglas,

Reading your posting... especially with your descriptions of "not being flush"... "angles off to the left", "screwed the retaining ring behind the standard on cockeyed" and "simply jammed on tight..."

If I were in your shoes, I'd be sending this lens into someone like S.K. Grimes or the repair person Drew mentioned in his posting.

Personally speaking, I wouldn't be trying to screw it off with a spanner wrench either. You may inadvertently strip the threads even more.

Just my 2 cents worth!

Best of luck on resolving this problem.

Cheers

ic-racer
2-Dec-2011, 19:00
Crossthreaded. I'd Dremel it off. Trying to unscrew it could just bugger up the lens threads more.

Douglas Henderson
2-Dec-2011, 23:23
Thank you for the responses. By "monkeying" with the ring, I meant I was using a spanner wrench--as carefully and as forcefully as I dared. The term "cross threaded" does seem to apply. The jammed ring is not even on the same plane as the threads--and trying to get it off looks to make things worse.

Sending it off to someone with experience is the smartest thing to do. Dremel is the cheapest--right up until I do real harm. Beautiful little lens and camera.

Drew Bedo
4-Dec-2011, 07:17
Douglas: Please let us know how this turns out.

May I highjack this thread for a related story?

In the 1990s I acquired about ten Wollensak Ocillo Raptars (75mm/f1.9 in a #3 Aliphax shutter) for next to nothing. All had come from salvaged-discarded Tektronix oscilloscope cameras. Each of them had a large aluminum collar screwed onto the outside of both the front and rear lens barrel.

I tried every method mentioned in this thread to remove the collars; penetrating oil, heat, and finally a bench vice and Vice-Grips combined with sweat and strong language. Nothing worked. I disassembled the front and rear lens cells (with attached collars) from the shutters and went to a gunsmith. After talking some he agreed (he didn’t want to do it at first) to chuck up one of the lens elements in his lathe and cut off the part. He did it carefully and got the first one off with little or no real trouble. The glass was fine and the cell it was mounted in was too. Got him to do all the rest.

Over the years, I sold off most of these lenses during the hay-day of the old Houston Camera Show. Still have two that I have used once and a while for macro work.

Douglas Henderson
4-Dec-2011, 20:32
I haven't got my courage up yet to dremel the ring, but that is probably what I will do--very carefully. Will probably isolate the drill field from the rest of the interior bellows and element glass with plastic wrap, tape and stiff paper--to keep the metal dust out of the bellows.

Since the above adventure began, I received a Balda Baldix 6x6 that needs a tiny lever replaced up inside the advance knob in order for the film to be wound at all.

And I received a Nettar 518 (have been on a folder craze of late) that couldn't focus anywhere near infinity--apparently because the last person to monkey with the glass had screwed the rear element too far down into the lens barrel. At first, I thought the rear element had been put in backwards--as it was, the camera could have made a slide projector, it projected such an enormous image when shining light through the lens out the back onto paper, focusing the light bulb only a foot away.

Once I screwed the element back up a bit to more resemble the position seen in some posted Ebay shots of the back of a Novar F4.5 75mm lens, the camera looks to be getting back to being usable. I hope. With some light tomorrow, I can try to adjust the rear element to focus the Nettar to infinity.

I never had this much wayward camera parts with large-format.

Uri A
6-Dec-2011, 01:12
If you want to try another avenue before you grind, try a steel rule instead of a wrench. Much more grip & torque available. Much less chance of skewering your hand or shutter too...

Douglas Henderson
6-Dec-2011, 14:31
Just for the record, the Nettar rear element is not the problem--it is seated in the barrel and all I was doing was raising the retainer ring. The problem may instead be that the middle element was placed in backwards from someone's earlier cleaning. Can't fix this until I get a spanner wrench with pointed posts. And if that's not the problem, I'm out of explanations.