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Damaged screw head


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Hi.  I picked up a fossil watch for a couple of pounds that hopefully only needs a battery, but one of the screws on the back is almost rounded off and doesn’t want to budge.  What’s the best way to deal with this?  The case is plastic so the screw is not rusted in.  I’ve resisted the temptation to put any sort of lubricant on it until I know what I’m doing.  Spa you suggestions would be gratefully received.  Thanks,  Al.  

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Hi  If the screw head is accesible try to cut a groouve in it with a fine knife edge  file to ceate a slot. Its not beyond some people to glue in a duff screw.  With a plastic case be very careful what you use to loosen the screw.  Be assured some body on the forum has had the same problem and will know of the way to proceed. good luck

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Thank you for the reply.  Its a bit of an odd solution, but I wonder if anyone has tried solder to build up the screw or even soldering a screwdriver to the screw to gain grip.  I’ve got a colleague who can solder joints that I can barely see, so if it’s worth trying, I know just the man to ask.  Good idea, or not?  

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Hi  trying to solder a screw which is encased in plastic is frought with danger as the heat from the iron would cause the plastic to melt and worst case ruin the watch  proceed with extreeme caution if you follow that route. Another possible is to use a dremel and drill the screwhead off leaving a small stub to be removed with pliers

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Thanks again for the replies.  I’d arrived at the “drill it out” solution but I’m still reluctant in case I can’t get the stub out.  I suppose, worse case it may end up with 3 screws holding the back on which isn’t the end of the world.  I hope it only needs a battery. Cheers.

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Being plastic it shouldn't be overly tight. You can try using a flat blade driver with a sharp edge to help provide the grip on the edges as you loosen.

If it won't budge at all then carefully and slowly grind the had with a dremel. This will leave a stub protruding once the back is removed which should come out easily.

In assuming you've loosened the other screws and confirmed it is screwed down and they're not moulded in cosmetic heads?

This often happens with fashion watches and they're a pop off case back.

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  • 3 weeks later...
13 minutes ago, mlfloyd1 said:

By some screw extractors from Esslinger.

A screw extractor may work (assuming it's a real screw) but is kind of pricey for an one-off job on a doubtful watch..

BTW Esslinger is an US seller.. I gather the OP is in the UK. 
 

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