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As shown above, I cannot unscrew anymore the screw of a Canon 70-200mm... :

  • What tool, technique, could help me get it out ? (before I start drilling into it...)
  • Where can I buy brand new screws to replace it ? The kind of small screws that are on Canon lenses...
  • 3
    Fit for diy.stackexchange.com – Esa Paulasto Aug 8 '13 at 8:23
  • @EsaPaulasto: indeed ! I didn't know it... Thanks !!! – Skippy Fastol Aug 8 '13 at 13:54
  • The end of a small screw-extractor bit should fit right into that divot to back the screw out. The problem will be to locate one small enough. Visit a watch repair shop. – Stan Sep 12 '13 at 17:04

Ouch that looks pretty stripped, but I have had reasonable luck using a rubber band. Place it over the screw head and then press your screw driver into it (push hard) and turn very slow.

Failing that if you don't want to drill you can try adhering a nut head to the screw (wait till it is fully cured) and then use a socket to back it out.

You can try searching online for a vendor to sell you the small screws. Canon also has a parts department (732-521-7230) that might be able to help.

  • Thanks for the comments. I don't know what a nut head is :( Thanks for the parts department number ! – Skippy Fastol Aug 8 '13 at 7:47

The traditional answer is to follow traditional stripped screw advice. Use super epoxy (very carefully) to adhere a new surface that you can loosen the screw with. The trick is to make sure you use enough to give you the necessary adhesion, but not so much that it adheres to the case in which case you are royally screwed. (Pun not originally intended.)

This link has a number of other suggestions as well, though not all of them would work well on a lens. It might also be worth simply cutting your losses and sending it in to be repaired by a Canon tech before more damage occurs. It'll cost more than if you succeed at removing it, but be a lot cheaper than if you have to send it in after failing.

  • no pun in ten did... I prefer to fail but to try. Additionally, I just bought it for $130 instead of $500, just because the focus ring is not "hyper smooth". – Skippy Fastol Aug 8 '13 at 7:45
  • @SkippyFastol - ah, so we're talking a used, non-stabilized 70-200 f/4 then. Yeah, that makes a big difference in terms of risk. I'd probably try that one myself too. I'd try some liquid weld adhesive to a small nut then and see if that gets it out, maybe the rubber band one first, but based on the picture, I kind of expect you will need the epoxy to get it. Good luck. – AJ Henderson Aug 8 '13 at 13:37
  • the strongest glue I know about is the cyanolite one. Never had the epoxy one. Gonna look for it..,. – Skippy Fastol Aug 8 '13 at 13:59
  • @SkippyFastol JB Weld is one of the common brand names for it. – AJ Henderson Aug 8 '13 at 14:15

Another approach is to use a center punch or a tiny chisel (and hammer) and use it to drive the screw to loosen.

I would strongly recommend not trying to drill it out. If you must try a drill, get a left-hand bit and use your drill in reverse rotation. This way, the drill will loosen the screw when it bites in. This may be enough to remove it without having to actually do much drilling.

  • Thanks for the trick. I'll have to find a left hand drill ! – Skippy Fastol Aug 8 '13 at 13:55
  • 2
    Trying to drill it out is very dangerous. You will have to use a tiny drill bit, and they are easy to break. When you break it, you will have a hardened steel bit broken off in a soft steel (or maybe brass) screw which is stuck in a plastic or soft metal part. This is nearly impossible to undo. Try the chisel or punch approach first. – Pat Farrell Aug 8 '13 at 14:36
  • Usual way to unscrew a stuck screw is to drill a hole in it and then screw a lefthand screw in the hole. These tools are sold in a box for solving just this kind of cases. But I've never seen small enough set that could help with screws of the size used in camera lenses. – Esa Paulasto Aug 8 '13 at 14:46

I have a rebel XT, tried the epoxy idea, which didn't work and I had to drill some of the screws. You could drill with a bit smaller than the head of the screw until the head comes off. Then you can use needle nose pliers to remove it.


Thinking a little bit outside the box here, this is a standard jewlers problem. Talk to your local independent jewler and see if he can offer a good price to remove the screw and then order the correct part from cannon before he gives it a try.

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