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Vintage Jewels


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Hi all,

I have a 1915 silver trench watch which has a cracked jewel on the bridge side of the 3rd wheel. From other forums I'm pretty certain that the movement is by Marvin, but it isn't signed which seems normal.

The jewel is rubbed in and i have acquired a set of opening/closing tools, but I don't know how to get hold of a suitable jewel.

I haven't removed the old jewel as the watch does run and keep reasonable time following cleaning and oiling, but i am reluctant to use it for fear of damaging the pivot and it does stop periodically. The pivot diameter is 0.2mm, and the outer diameter of the jewel seems to be about 2.3mm (the closed metal over the jewel is about 1.6mm in diameter).

Am i better off waiting for a used movement to come up on ebay, or buying one of the multipacks of jewels that appear on there... Or is there a great source for vintage jewels by size??

Thanks for your thoughts...

S

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if you end up really stuck, I have a couple of boxes of sized vintage jewels, though not every size. if you know the exact size I probably have one that I can happily send you. Based on your measurments that would make the jewel a 20 210, having just looked through my jewels, the closest I have to that is a 26 200, so 0.26mm by 2mm.

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  • 2 weeks later...

Hi All,

 

I went to visit a local watchmaker who specialises in vintage watches and clocks today.

 

He couldn't offer me a jewel, but his advice was to track down a similar movement to harvest a jewel out of.  He has tried to buy selected assortments of jewels, but what I need is a popular size and the selections that come up on ebay are all the unpopular sizes.  More hours on ebay looking for trench watch movements - since the movement doesn't carry a makers name, this will be easy (not)!

 

He did also give me another interesting piece of advice which I don't recall hearing before.  Since the pallet jewels are somewhat worn (with a track running across them) he said I should make up a brass jig to hold them at the right projection length, so I can heat them up and move them down slightly in the pallet to use a fresh surface.  This should improve the impulse action and therefore the timekeeping  Anyone ever tried this?

 

S

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