Screw-in lens cap frozen or jammed - fix?

[jay moussy]

A bit of a silly ebay purchase, a Spotmatic body I wanted (so I have two).

That came with an M42 Super-Lentar 35mm 2.8 (A Tokina issue?) and a screw-in lens cap that is solidly on, and seller may has unscrewed the last metal ring the filter thread is on (and in doing so made the last glass lose!)

So I have the last metal ring, off lens body, with the cap on, forzen, cross threaded or with particles caught in threads.

Best way to deal with it?

Notes:
- the lens is probably not a great value (but maybe a nice beater?) so I can be adventurous
- screw-in cap could be dremel'd out... carefully.
- I am soaking in 90% alcohol right now

 

[madNbad]

You might try a jar lid removal tool. They're designed to fit a variety of lids and would give you the leverage to break it loose.

 

[jay moussy]

Well, a trip to the small vise downstairs, and the cap is off!

Next is clean with alcohol again, inspect thread and test with a 46mm extension ring to check thread integrity.
And also test lens.

 

[Sirius Glass]

A wide rubber band or even better is a filter wrench.

Amazon.com : lens filter wrench

Do not leave home without them.

 

[Don_ih]

I'm glad the vise worked and you didn't have to put the torch on it.

 

[Rolleiflexible]

I once had the same problem with an early pristine 85/2 Nikkor-P lens in LTM mount. After trying everything that seemed safe, I took it to Nippon Photo Clinic in Manhattan. They got the cap off and charged me $40, which I was more than happy to pay.

Note to self: No more screw-in lens caps.

 

[Xylo]

I know that when it comes to broken filters, it's always safer to cut the filter ring with some snips and unroll it with some pliers. But a metal cap would involve dremeling.

Note to self: No more screw-in lens caps.

Plastic ones would probably be the safest... but I prefer clip-on ones when possible.

 

[Sirius Glass]

Clip on the thread lens caps can be used instead of screw on caps.

 

[250swb]

The problem even with a solid screw on lens cap is that as soon as you grasp them hard you distort them, like a filter or a lens hood stick on a lens. So try either being very, very gentle unscrewing it without doing anything ham-fisted, or press the lens cap onto something like the neoprene side of a mouse mat and turn. It's about spreading the grip on the cap perfectly and not a biased grip. With a filter you can cut two opposite slots into the rim and use a length of metal (steel rule) as a very wide screwdriver, not so easy with a lens cap but if you can work out a similar work-around it would probably work. Naturally mask off any vulnerable parts of the lens if you are grinding or filing but you usually end up saving the filter or lens hood as you take it off.

 

[ant!]

since my problem with a stuck macro extension ring sounds similar (I should have posted it in "repair" instead of 35mm probably), any tips for me? Here my thread: https://www.photrio.com/forum/threa...-extension-how-to-remove.200405/#post-2702505
I think on getting a lid removal/strap wrench as the next step. Maybe two, one for the lens and one for the ring?

It seems like it wiggles now a 1/3 mm back and forth, but is still stuck. Rubber bands alone wasn't working

 

[Dan Daniel]

I have found these filter wrenches to be very good for both filters and for lens group removal. They are made with a heavy spring metal rod shapped as shown and then coated with a thick grip material. The coating is a bit like the latex on work gloves. You'll need to find the right size, of course. Much much better and stronger than the plastic filter wrenches.

[edit- not sure waht is going on but the link is not showing for me. Go to Amazon and search for '

Neewer® Rubber-Coated Metal Camera Lens Filter Remover Wrench '​

 

[ant!]

Do you think these filter wrenches are strong enough for my macro ring (see post just above)? The neewer is at least metal, not like some others from plastic. Since the grip area I have is narrow, it might actually be better then a strap wrench. I guess I'll have to try it out...

 

[Dan Daniel]

I can't promise, of course. The wrenches are fairly strong and allow for a tight squeeze. Unlike the plastic ones that will 'fold' if too much pressure is applied.

I've found that the red rubber sheet gasket material sold at hardware stores as the first layer inside a filter wrench or strap wrench can also be a big help. Especially if the part has projections or bumps like a bayonet filter.

And then double sided tape can give a good added grab. Sometimes it allows for less pressure from the wrench itself so there is less chance of distortion. Sometimes it's after pressure is let up and you lightly turn that the item can unscrew.

 

[ant!]

I got that macro ring off! I had stuck it in the freezer over night, just to try that out. When I took it out and it was still cold, still no success with two rubber bands. So, now just before ordering the filter wrench, another try with rubber bands, and it just sled off. No idea if the cold and warm up help, or the rubber bands were any different, or me holding it down (not really strong) on a mouse pad, it was in the end not tight anymore.

 

[MattKing]

If my wife had been there, she would have said: "I loosened it for you!"

 

[Rolleiflexible]

If my wife had been there, she would have said: "I loosened it for you!"

She’s right, you know.

 

[Sirius Glass]

I got that macro ring off! I had stuck it in the freezer over night, just to try that out. When I took it out and it was still cold, still no success with two rubber bands. So, now just before ordering the filter wrench, another try with rubber bands, and it just sled off. No idea if the cold and warm up help, or the rubber bands were any different, or me holding it down (not really strong) on a mouse pad, it was in the end not tight anymore.

Another satisfied customer member!

 

[Udor]

A while ago I had the same problem. I tried everything, and nothing seemed to work. Then I found a magic solution (as a last resort): use ice to cool down the lens cap considerably, and then it will come off (but be careful not to get water into or around your lens). A few seconds of contact with ice did the trick. If you live in a cold climate, bringing your lens outside in the winter can do wonders for this kind of problem.