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Screw extraction (broken screwhead)


IFELL

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Hi,

I managed to brake a screw which is holding the movement in the case.
Now, I don't really want to buy the dedicated Burgeon remover (~ £70), are there other ways to get it out?

The screwhead went completely off so I am left with just the shaft of the screw deep inside the hole.

I found these precision screw extraction drivers. Anyone has any experience with these? Are they small enough?
https://eustore.ifixit.com/en/Tools/Drivers-Wrenches/Precision-Screw-Extractor-Set.html?cur=1&utm_source=google&utm_medium=mc&utm_campaign=gshopping&gclid=CjwKCAjw39reBRBJEiwAO1m0OaeDhACGsOqhgZnLzupVcHbStZSTnsmvOMKcmOgg7A1dAOpEmdIvCRoCoWwQAvD_BwE

Thank you for any tips for other tools or techniques.

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You can sort of replicate what the Bergeon tool does with a staking set, get a stump and punch that will both fit in the threaded hole, and clamp the screw between them, then turn the entire mainplate around the screw. If the screw is really stuck it doesn't work so well, but generally once the head is broken off they have some freedom in the threads.

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Ok, 

I mount my soldering gun on a stand and heat up the screw only with it.

Meawhile fix a jar of cold water mix with bunch of ice cubes.

The water cools down as the screw heats up, at highest temp I drop quench the plate in the water. Reheat the plate let cool down to room temp, drop penetrating oil on the screw, come back next day to attack the mess I done made.

If it didn,t work, I blame it on vinn.   :geek:

Regqrds joe

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I don't know if it is my method (Probably is) but I have had not much luck using alum. Those screw extractor screwdrivers look good I mighty give them a try. I have the Bergeon screw extractor and have used it once. The method I have used is to drill out the old screw after flattening the broken screw head. This method has it's dangers IE is f the drill wonders off centre and only works with screws large enough to take a drill. 

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20 hours ago, Nucejoe said:

Ok, 

I mount my soldering gun on a stand and heat up the screw only with it.

Meawhile fix a jar of cold water mix with bunch of ice cubes.

The water cools down as the screw heats up, at highest temp I drop quench the plate in the water. Reheat the plate let cool down to room temp, drop penetrating oil on the screw, come back next day to attack the mess I done made.

If it didn,t work, I blame it on vinn.   :geek:

Regqrds joe

     i'll take all the resonsability,  IF  the proper penetrating oil was used.    vin

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I have not seen much less use alum, but regard it credible since OH introduces it.

I would say, what time and other costs I would put in, much depends on the piece,  not just the material but the price as well.

The thremal expansion of the screw and pursuent contraction,  is to facilitate the peneteration of oil, as the heat if much conducted to the mainplate is to be transfered through the rust between the screw and the plate, that with the following contraction, breaks possible rust or other chemical bonds formed beteewn screw-plate.

Quenching is not expected to play a major role.

With all due respect to repair masters ,over all, oiling approach is superior to chemical dissolution of the screw, since gold or chrome plating inevitably  got pores to make the mainplate vounerable to penetration of  chemicals, or tapping on the screw from both ends, since tapping would damages the thread in the mainplate too.

So if is a rolex or vacheron  , I would do at most to affect the screw only. if an Asian eta ...well.  

Regards joe 

 

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I have been successful using vinegar  (ascetic acid), it eats the steel just make sure you don't get any important steel bits submerged as it could damage them as well, leave it in the vinegar over night or until dissolved.

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