Oil on the back side of a Copal 3 shutter, is this normal? (Reference Pictures)

[zbvision]

I recently acquired a new lens and wanted to try it out on my v8. Went to disassemble it in order to mount it on a 6x6 lens board and found oil on the back side of the Copal 3 shutter just under the threaded screw mount. This cannot be normal. I have never seen anything like it with any of the other 4x5 or 8x10 lenses that I own. Should I even attempt to photograph with this lens? Is this sort of thing repairable?

[John Layton]

Very difficult to see from your photo...but maybe a bit of something "seeping in" from the left side, more visible in the second photo?

Question: does any of this "oil" find its way onto either the iris leaves or shutter leaves? (or both?). You might try first slowly opening and closing the iris to see if any oil finds its way there as you do this. Then do the same with the shutter leaves - using the press to focus lever.

If no oil shows up from doing the above...then you might try taking a bit of lens tissue or other absorbent material and seeing if you can use this to wick some of the oil away, then see if it keeps re-appearing.

If oil does propagate onto the shutter and/or iris leaves, then give it a sniff. If its smells "sweet," there is a chance that it might be WD-40, which if used in quantities great enough to cause such a spread might be cause for alarm. (Then again, WD-40, if allowed to sit so that its solids settle out, can be an excellent lubricant...but only when applied minimally).

Also, in the case of excessive propagation onto the leaves, see if the oil evaporates on its own, and if not, try gently wiping it away as much as possible before repeating the operation of the leaves, then do this a few times until (hopefully) no more oil appears. Then maybe turn the shutter upside down for awhile, and then repeat the operation. If more oil shows up again, then I'd be very careful about using this shutter without having it opened up and cleaned further. The problem with oil in such excess is that it can fly onto lens elements during use, and can then be difficult to clean off properly.

Considering the location of that dark strip of oil (if that's indeed what it is), it looks feasible that this might equate to an over-zealous oiling of the slow speed mechanism - which, when they begin to get sluggish...are sometimes removed, cleaned, and re-oiled by DIY-ers like myself, who can sometimes approach such projects with very little understanding of just how small an amount of lubricants are actually needed.

[zbvision]

Very difficult to see from your photo...but maybe a bit of something "seeping in" from the left side, more visible in the second photo?

Question: does any of this "oil" find its way onto either the iris leaves or shutter leaves? (or both?). You might try first slowly opening and closing the iris to see if any oil finds its way there as you do this. Then do the same with the shutter leaves - using the press to focus lever.

Hey John,

I have done as you have requested and can report that there definitely is NOT any oil on the iris leaves or shutter leaves. It seems to be dried, almost of a resin type of consistency and it is located in two crescent moon shaped strips that are equidistantly spread around the interior circumference of the back side of the shutter itself. Appears to be some sort of adhesive/weatherproof sealant that is adhering on one side to the ring around the back side of the shutter but before touching the iris and shutter leaves. The other side is seemingly adhered underneath the screw mount threads located on the very back of the shutter. Might be a bit wordy so I have attached 2 better quality pictures to the original post that started this thread. These will be the best photos I can muster up to give you a better understanding of what I am talking about and whether this is something to worry about or whether or not it is a "normal" part of the design of a modern Copal 3 shutter. I appreciate your input.

[Kevin Crisp]

Then use it, you're good. If the aperture blades and shutter leaves work fine.

[nolindan]

Sounds thread locker - probably a screw came loose and the owner/repairer (in general a bad combination - like being your own lawyer) decided those screws aren't coming loose again. Some choices for thread-lock for small screws is nail polish, glyptol or 'blue' Loctite.

I would leave sleeping dragons alone. It will harm nothing leaving it where it is. The time to worry about it (if even worry is justified) is when the shutter gets serviced.

[Neal Chaves]

That looks like the start of separation in the rear lens elements to me. If it is nothing will clean it off and of course the shutter blades will not be affected.

[zbvision]

Then use it, you're good. If the aperture blades and shutter leaves work fine.


Sounds thread locker - probably a screw came loose and the owner/repairer (in general a bad combination - like being your own lawyer) decided those screws aren't coming loose again. Some choices for thread-lock for small screws is nail polish, glyptol or 'blue' Loctite.

I would leave sleeping dragons alone. It will harm nothing leaving it where it is. The time to worry about it (if even worry is justified) is when the shutter gets serviced.

Hello Kevin and Nicholas,

I might add that I do not yet know whether the shutter speeds are accurate across the board. I plan on getting this lens benchmark tested for free. If the shutter speeds are not accurate and a CLA ensues, would I then be in trouble? Whatever the previous owner used to keep the screws from coming loose does not appear as if it can come off easily without doing significant damage to either the iris or shutter leaves. Thanks for helping me trouble shoot. Y'alls input has both been extremely helpful.

[zbvision]

That looks like the start of separation in the rear lens elements to me. If it is nothing will clean it off and of course the shutter blades will not be affected.


Hey Neal, how could that be possible? The rear lens elements are completely out of the frame in the pictures you are seeing. This has to do with the shutter itself. Both rear lens elements (not pictured) and front elements (pictured) are pristine, clean and clear.

[J. Patric Dahlen]

Sounds thread locker - probably a screw came loose and the owner/repairer (in general a bad combination - like being your own lawyer) decided those screws aren't coming loose again. Some choices for thread-lock for small screws is nail polish, glyptol or 'blue' Loctite.

I would leave sleeping dragons alone. It will harm nothing leaving it where it is. The time to worry about it (if even worry is justified) is when the shutter gets serviced.

That is what I'm thinking as well. It doesn't look oily or anything that is migrating.

[Neal Chaves]

Hey Neal, how could that be possible? The rear lens elements are completely out of the frame in the pictures you are seeing. This has to do with the shutter itself. Both rear lens elements (not pictured) and front elements (pictured) are pristine, clean and clear.

You are right, I guess I saw a reflection of the light used to make the photos. That other residue must be thread locker of some kind. As has been suggested, if it is dry and not spreading, just ignore it.

[BrianShaw]

Have you interrogated the smudge with a toothpick to see if it’s liquidy, gelatinous, or solid? Or a q-tip cotton swab ever so lightly moistened with alcohol or lighter fluid to see if it will wipe off?

That’s a very odd location for threadlocker. But no matter, it appears perfectly harmless…