Removing rear element from Copal #0 shutter

[lfbrown]

I have a lens in a Copal #0 which I need to mount. I cannot, however, get the rear element to unscrew. I've only had this problem once

before with a very old, second hand Graflex shutter/lens combo. In that case applying all my strength finally broke it loose - a strategy I'm

reluctant to use on a more expensive lens. I was wondering what methods others have used to solve this problem or if there are

"approved" approaches I'm unaware of. Thanks.

[dhbebb]

<p>Winding an elastic band around the lens should improve your grip.</p>

[rodeo_joe1]

<p>I'm betting that both the lens and shutter are aluminium. Ali on ali is never a good choice for threads and the slightest bit of corrosion can seize the threads solid.</p>

<p>If the above recommendation to improve your elbow power with a friction spanner doesn't work, then much as I hate to see the stuff anywhere near to optical equipment; I'd recommend introducing a <em>small</em> amount of WD40 into the threads. Don't spray it in directly, but use a toothpick or the supplied tubing to drip a drop or two into the crack of the threads. Wipe away any that doesn't capillary into the threads within a few seconds.<br>

Let it stand for up to 24 hours and then try to unscrew the lens again. As soon as it frees (if!) wipe the thread again as it unscrews to ensure non of the pernicious WD40 gets into the shutter or on the lens.</p>

<p>Good luck!</p>

[lfbrown]

I got it. Wasn't as tight as I thought. A

better grip and fingers did the trick. I

appreciate the tips for future reference,

though.