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Wayne
8-Feb-2004, 21:21
I decided to remove the lens from my Betax while I work on it because it looks like it needs more than just a Ronsonal wash, and I have an Alphax laying around thats in better shape. The front lens/barrel unscrewed easily and screwed right into the Alphax, but the rear tube (its a T-R convertable) will not budge. I've tried the sheet rubber trick (pressing down and turning it on rubber) to no avail. Its REALLY stuck. Is there anything else I can try?

Ernest Purdum
8-Feb-2004, 21:47
A "strap wrench" is the tool usually successful in this sort of case. This is a piece of high friction material, such as leather, wrapped around the cell. A handle of some sort gives leverage. Commercial strap wrenches are available, but most of them are made for plumbers and are too wide for lens work, so you will probably have to improvise something yourself. You might look at a commercial one, though, to gain an idea of how it might be made.

Paul Schilliger
9-Feb-2004, 04:36
There was a recent discussion on that. “Just watch you don't wear out the threads trying out all these ideas :~)” said Otzi.

http://www.largeformatphotography.info/lfforum/topic/497444.htmlby

Doug Pollock
9-Feb-2004, 08:57
I use the Handi-Grip Lens Wrench. Handi-Grip is available through Fargo Enterprises at www.microtools.com (http://www.micro-tools.com) at $19.95. I am not associated with Fargo Enterprises in any way. They also offer three different camera toolkit collections!

Jim Galli
9-Feb-2004, 09:14
Chuck the barrel in a lathe, put some leather gloves on and crank. You can get a dissimilar metal reaction going in these pre-war pot metal items that can ultimately preclude disassembly. I destroyed at least one Ilex 3 shutter with stuck group. Can't remember what the lens was anymore. Maybe an Oscillo.

Paul Schilliger
9-Feb-2004, 12:03
Ultimately if the thread is cranked, I would infiltrate a few small drops of antigrip solution in the join and let it work for a few hours. But it should be very very sparce, almost dry, otherwise it could get into the glas elements.

Wayne
9-Feb-2004, 14:43
Arggg. It turns out the barrel is cross-threaded into the shutter. Gee, no wonder its stuck! Its unlikely that it can be removed without damaging one or the other.

Jim Galli
9-Feb-2004, 15:27
Yes, but it'll be good for taking pictures around corners. :-()

Wayne
15-Feb-2004, 12:37
I took the lens to a camera repair guy and he couldnt get the barrel off either. So I decided to take one more crack at it, using a (gasp) vise (hey, they are metal shutters) and pipe wrench. Voila! The barrel came off unscathed, though the threads on the shutter are funked up.

Trivia fact: I did all of this so I could put this lens right in my Alphax of the same size. But (i now know) the rear threads on a #4 Alphax are not the same size as the #4 Betax! Who'da thunk it....The front and rear of the Betax are identical to each other and the Alphax front, but the rear of the Alphax is larger. Now you know.

John Kasaian
15-Feb-2004, 12:52
How funked up are the threads on the shutter? It might be possible to restore them to usefulness with a file thats made for restoring threads. I think I saw one in a Centaur Forge catalog awhile back.

Good Luck!(sounds like you already had your share of bad luck!)