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measuretwice

Help with Jewel Repairs in a Dial Indicator

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I posted here because its not a watch repair, but the techniques are the same or similar.  I've some cracked jewels in a nice German 1/10,000" dial indicator.  They're reminiscent of old style rub in jewels in chatons, but there's not really any sort of lip or anything else where you'd close it in to hold the jewel.   So the first question is how is the jewel held in the brass chaton?  Cement?  would it just press out?

The second question is where does one get large size jewels like this?   OD of the chaton is 3.5mm, Diameter of shaft going into the jewel is 1mm.   Buy blanks and turning the down is a possibility, but not sure where to source blanks.  The value of these old indicators isn't so high that there's a big budget, so it probably needs to be a low cost source of jewels - unlike a Rolex, if you start spending $20 each on a couple of jewels, its not worth it.

I could just turn bronze bearings, but of course ideally I'd like to keep its original quality and performance with jewels

I've got several instruments with similar requirements, they've been waiting for a stroke of genius and there's been none!  any ideas welcome, thanks

PS, in looking for ideas I came across this video and was really impressed - this guy does rub in jewel replacements including home made tools and grinding them to size...all with a dremel!! 

https://www.youtube.com/watch?v=j3gxp96WjCI

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