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Stuck cap jewel


JHargrove77
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Howdy gang,

Need help with a little problem I'm having.  Working on a 1930 Elgin 12s pocket watch that had a broken balance staff pivot.  I need to remove the cap jewel so I can test the fit of the new staff in the jewel hole.  I've removed the screws but have been unable to get the cap off.  Looks like it may have been a tight fit from the get go and someone pressed it in before inserting screws.  I included the dime in the picture to show scale of what I'm working with.  There's no gap that I can find to pry on and rodico doesn't work.  I tried some sticky tape but no luck.  Any suggestions on how I can grab it?  Not sure how much effort it's going to take to dislodge it. Don't want to damage it.

capJewel.jpg

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These are a light press fit, along with a setting below holding the hole jewel. It should be pressed out from the underside. They used to sell star shaped tools with different diameter brass pieces  that were used for pushing out these jewels. If you have a jeweling tool that's perfect.  But pegwood works fine except for very stubborn ones

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Be very careful. I've broken one before. Your staking tool must rest on the brass chaton, not on the jewel. If you have a Seitz jewelling tool, that's even better.

Over tightening of the 2 retaining screws could have deformed the chaton but I believe that the brass chaton deformed over time due to molecular creepage and became stuck. Some of these pocketwatches are over a hundred years old! 

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Would the upper jewel set in the balance cock be pressed in the same way?  I removed the screws from it also just for cleaning and oiling and it doesn't want to come apart either.

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It varies. Sometimes the screws are on the underside of the balance cock and you'd have to unpin the hairspring and remove the balance wheel to get to it. It's a real PITA. Never understood why they were designed that way.

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43 minutes ago, HectorLooi said:

It varies. Sometimes the screws are on the underside of the balance cock and you'd have to unpin the hairspring and remove the balance wheel to get to it. It's a real PITA. Never understood why they were designed that way.

Except for really cheap and/or cylinder movements you can release the stud, no need for unpinning the hairspring. Most non-shockprotected watches have the hole jewel in the cock, cap jewel set in a disc that holds the regulator, screws from underneath. Really old and pocket watches, screws from the top sometimes; American and Swiss emulators, with screwed down settings for both cap and hole.

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Just to update the group, I was able to remove the jewel set by pushing from the hole side.  Both popped out without incident.  I found an Elgin Watchmaker class PDF on line that showed how it's put together.  I want to thank nickelsilver for pointing me in the right direction.

elgin.JPG

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