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Jewel holes Rub in

BillF

By BillF
in Watch Repairs Help & Advice

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BillF Member

BillF

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Hi

Im having great difficulty getting hole jewels for bridge on a Tavannes pleaded pocket watch they are rub in type, not straight sided. Have googled searched ebay for weeks but no joy. Is it possible to adapt bridge to use a straight side push in, friction jewel instead of the rub in ones. 

I have also looked for a donor watch or a bridge but no joy there either 

Thanks 

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Tmuir Distinguished Member

Tmuir

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Rub in jewels do turn up on Ebay, but are rarely listed as rub in jewels as usually the person selling them does not know the difference.

Just keep searching for watch jewels and you will eventually find some, but whether they will have the size you want is another story.

 

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nickelsilver Distinguished Member

nickelsilver

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You can ream out the old rub in setting and put in a friction jewel. The issue is the new  jewel is now significantly bigger in diameter than the original and it's unsightly. Sometimes you can get a friction jewel in the old setting and manage to re-rub the brass and it will hold. Rub in jewels are out there, like Tmuir said, but they are often a jumbled assortment and it can be a real trick to find one that matches both the old setting and the pivot.

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WellAdjusted Member

WellAdjusted

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From a restoration perspective, the proper approach is to "rub in" another jewel. You can open up the thin lip that secures the old jewel (with a lathe or with some jewel opening/closing tools), put a new jewel in, and then close up the lip again. Those tools pop up on eBay on occasion and sell for a lot.

It is not as hard or daunting as it sounds. Fried's books (either Watch Repairer's Manual, Bench Practices..., or both) give a good tutorial and breakdown.

But from a practical perspective, do a search for "friction jewel converters."  I have an example of using them here on a old 7-jewel watch I worked on for fun with my son.

The converters solve the problem noted above, that jewel settings are huge, and putting a friction jewel of the same diameter in the plate looks really weird.

The friction jewel converters look like a setting. You ream the inner hole of the converter to the jewel diameter (if necessary), friction fit the jewel in the setting, and then friction fit the setting in the bridge.

Edited by WellAdjusted
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nickelsilver Distinguished Member

nickelsilver

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I had no idea anyone had produced "friction jewel converters" ! Haha. I have made them many times though. It's a quick lathe job, and when done neatly you have to take the bridge off and look underneath to see that there isn't an original rub in jewel in a rub in setting. Having nickel bar is handy at it blends very well in german silver movements, for a high end gold plated movement with a visible setting the converter gets plated.

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