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Posted (edited)

I'm repairing a Movado cal 150MN. Just fitted a new balance staff and noticed the lower balance hole jewel (non Inca) needs replacing.

I need 0.09 hole x 1.30 mm diameter.

Cousins list 1.30, 1.40, 1.50 mm diameters as discontinued. 

In my selection of old jewels I found 1.2 mm diameter jewel.  Is that too much to close the hole ? - the plate is reasonably thick at the jewel.

(Just found Ofrei stock them)

 

Edited by mikepilk
Posted

Yeah you'll never close the hole 0.1mm, 0.01 is hard enough. I'll have a look what I have when I get in the shop.

 

Otherwise, you can ream to 1.40, or, take a smaller jewel and make a thin walled bushing to fit the original hole. I do this frequently, no harm to "originality" and 100% functional.

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Posted

Unfortunately the 1.40 and 1.50 mm are out of stock (discontinued) at Cousins too.

Thanks for the offer, but I've just found some of the right size in the UK - HS Walsh. Their website is useless, but found it on ebay.

9 minutes ago, nickelsilver said:

or, take a smaller jewel and make a thin walled bushing to fit the original hole. 

Most of the other jewels in the watch are in brass bushings. I had thought of that,  but without a lathe ...... 🥴

It must be tricky making such small bushings on a lathe and pushing them in without damage.

Posted
3 hours ago, mikepilk said:

Most of the other jewels in the watch are in brass bushings. I had thought of that,  but without a lathe ...... 🥴

It must be tricky making such small bushings on a lathe and pushing them in without damage.

either available separately or on the top left hand of the large set of  Seitz  tool. Although I would've been nice if it was somewhere else because the little tiny collets like to jump out of the hole and get into the hinge and break themselves which is quite annoying when you come time to using the tool properly but there are ways around that. or basically they realize the problem we would have and they have bushings. here's an image from the catalog of how you're supposed to do it.

In my particular case because I didn't have the collet I just took one of the bushings the right size sanded slightly on sandpaper suit was thinner shoved it into the main plate reamed it out for the jewel I was using and I was good to go. Yes the real timesaver we need a bushing a don't feel like making it on the lathe.

image.thumb.png.9e1d6e16c3a72678387de9f44209acbd.png

probably these have been discontinued like everything else you may be able to purchase a clock bushing and if you're careful modify that because there are some really small clock bushings although it would be much better if you had a lathe.

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