Copal Press Shutter

[Ceebee]

Hi, I have a Polaroid Press shutter with 75mm Tominom mounted in the Polaroid close up attachment with the ring flash. I am trying to remove the lens and shutter to use just the shutter but am having problems. I have got the inner mount out of the box with the ring flash to reveal the locking rings, one for the shutter the other for the rear cell ? but both seem to be locked solid. Has anyone removed similar ? have I missed something obvious like grub screw, can't see any, or right hand threads ? Thank you in advance.

[Dan Fromm]

There's no locking ring for the rear cell. It should screw right out of the shutter.

I've extracted lens/shutter assemblies from several Polaroid CU-5s. The shutter's retaining ring should screw right off. You'll need a proper spanner, may have to apply a little force.

[LabRat]

I just worked on some Polaroid Copal/Prontor lens & shutters a couple of weeks ago... I seem to remember that at least one of them had some thread lock applied to the threads...

No problem, first look carefully at the rim around the mating surfaces to see if you can detect a tiny blotch of the dried goo... If so, go to the drug store, farm feed supply, or ask a diabetic friend for a hypodermic syringe... Then get some acetone, or nail polish remover and suck a very small amount up into the syringe... Then carefully apply the smallest droplet from the tip into the seam where the threads meet, esp. in the goo area... Let it sit for a few minutes, then repeat 2 or 3 times over time... This will soften the thread lock, and allow the threads to turn with a spanner wrench...

Careful not to get the acetone onto any painted or plastic surfaces as it can damage the finishes...

What goes in, must come out... (somehow) If it does not turn with reasonable force, go to plan B... (Stare at it for a long time until you figure it out!!!!)

Good luck!!!

Steve K

[Old-N-Feeble]

Won't acetone melt the plastic barrel of the syringe?

[Jim C.]

Won't acetone melt the plastic barrel of the syringe?

Injection syringe bodies are polyethlene, the acetone will swell the rubber plunger.

Anyone remember the drafting ruling pen ?
Those are great to hold a drop or two of anything, a straight pin also works for applying tiny amounts.

[Ceebee]

I suspected thread lock, so I've got hold of some acetone and will fabricate a more sturdy tool to cope with the reach and have another go this weekend. Also found detailed drawings of the parts so will post link later.

[DrTang]

I just worked on some Polaroid Copal/Prontor lens & shutters a couple of weeks ago... I seem to remember that at least one of them had some thread lock applied to the threads...

No problem, first look carefully at the rim around the mating surfaces to see if you can detect a tiny blotch of the dried goo... If so, go to the drug store, farm feed supply, or ask a diabetic friend for a hypodermic syringe... Then get some acetone, or nail polish remover and suck a very small amount up into the syringe... Then carefully apply the smallest droplet from the tip into the seam where the threads meet, esp. in the goo area... Let it sit for a few minutes, then repeat 2 or 3 times over time... This will soften the thread lock, and allow the threads to turn with a spanner wrench...

Careful not to get the acetone onto any painted or plastic surfaces as it can damage the finishes...

What goes in, must come out... (somehow) If it does not turn with reasonable force, go to plan B... (Stare at it for a long time until you figure it out!!!!)

Good luck!!!

Steve K

or use the crude-o-man method: stick the blade of a screwdriver into the slot closest to the gob of threadloc.. while holding lens tightly..smack the handle of screwdriver with a hammer...this will usually crack the gob.. and then you can unscrew the lens

[Ceebee]

Threadlock....applied Acetone wouldn't move, applied some more and went away, wouldn't move, some more and spent an hour hand filling a tool to fit, came back to use tool and the ring just shifted as i placed tool onto ring..for those interested diags. here http://everythingretek.com/PRDLibrary/LIBRARY8/LIBRARY/PARTS/CU5CAT.PDF