Buying jewels

[tpmcan]

Rookie question. I’ve got a growing collection of Ebay movements that all seem to have a cracked jewel here or there. I’ve found new Seitz jewels at places like Otto Frei but where does one go for a jewel that’s in a brass or other metal setting? Do you have to make your own? (Just getting into the lathe lessons).

[Bob Tascione]

Welcome to the forum tpmcan!
There was a time when it was fairly easy to purchase the jewels in their settings just by giving a few details like the names and model numbers for the movement to a parts house. Much more difficult now but I think there are still some guys out there selling jewels in settings. Maybe someone up here knows of someone. Most of us have purchased assortments over the years and can dive into them when needed. There are times though when you’ll need to make a jewel setting. With a little lathe work experience behind you it’s an easy task just to copy and duplicate an existing setting.
I’ve just emailed you some pdf files that may help you understand how rubbed in plate jewels (and friction jewels) can be replaced and how settings work.

Enjoy,
Bob

[tpmcan]

Thanks Bob. I had been through the Chicago lessons already and they didn’t really address “bezeled” vs “non-bezeled” jewels or those that came in settings and those that came naked. So the take-home lesson is there is no readily available source for these now unless you are proficient with a lathe. For sake of discussion I came across this last night in the Bulova school lessons (unit 9B). “In the last few years, the leading watch manufacturers have adopted the improved system of friction jeweling in place of the older and less efficient method of setting the jewels in individual brass or gold settings…the friction jewel is more rugged than its predecessor, the bezel jewel.” Guess I will have to live w/ some cracked jewels until I get a lathe and learn to use it. Along the same vein, when ordering new jewels one of the parameters needed is the outside diameter of the old jewel. If the old jewel is in a brass setting, what is the preferred method of getting the brass off to take an accurate measurement?

[Bob Tascione]

Tpmcan,
You’ll find that info in lesson 12. I included the other 2 lessons just so you could compare the different types of jewels. You would press the jewel out of the setting much the same way that you would with a beveled plate jewel. If you have a bezel opener you would then open the bezel up the rest of the way and measure the diameter of the opener. That would be the OD of the jewel. If you want to replace into the same setting you would need to either find an old style bevel type jewel or modify a new press fit jewel. If you can locate an assortment of old bevel edged jewels up on ebay or where ever then by all means grab it if you can. If not you can grind a newer jewel to fit. Not as hard as it sounds but again you’ll need a lathe. Actually that’s not 100 percent accurate as you can actually do the job on anything that spins that holds close tolerances.
Anyway take a close look at Lesson 12 and think settings rather than plate jewel setting. It shows how to determine hole size as well.

Have fun,
Bob

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