...have searched the archives for an answer and after having tried several 'headings/ w/o success, would like to pose the following question...is it possible to re-use/re-furbish the setting of a cracked jewel...and if so, how does one go about it?...that is to say, remove the damaged jewel and replace w/another...thanks...watch 'newbie'...Jim

Jim,

There are essentially two different types of jewel settings: burnished settings, and friction settings. Since friction jeweling is very simple, I'm going to assume that the type to which you're referring is the old fashioned burnished type.

It IS possible to replace a jewel in an original setting, but it isn't easy. Of course, before attempting the job, one needs to have an appropriate replacement, and for that, there are essentially four different aspects to consider: the size of the jewel hole, the outside diameter of the jewel, the thickness of the jewel, and the color of the jewel. Obviously, the color isn't a "functional" element, but it looks terrible to put a bright red synthetic jewel in a watch where the rest of the jewels are pink or colorless.

In any event, the best way to get a broken jewel out of a bezel, is to force it out with an appropriately sized staking punch. With the jewel removed, a "jewel bezel opener" is used to open the burnished edges, then the replacement jewel is inserted, and a "jewel bezel burnisher" is used to close the bezel again. During the opening and closing process, I find it best hold the jewel bezel in a lathe chuck, and turn it in a watchmakers' lathe. Using a bit of oil helps to hold the jewel in place, as well as to reduce the chances of "galling" the metal.

Needless to say, the process requires the appropriate tools, as well as a significant amount of skill, and even under the best of circumstances, success cannot be 100% assured.

Many instructional books have sections on jewel replacement, but if you want more detailed information, let me know, and I'll try to make some sketches and post them here when I have time.

Hope this helps!

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Steve Maddox
President, NAWCC Chapter #62
North Little Rock, Arkansas

...thanks Steve...appreciate the response...while I appreciate the difference between 'burnished' and 'friction' settings (in fact re: the former, I've ordered a set of combination jewel bezel 'openers/closers/burnishers), I was concerned more with re-using brass, or more importantly, gold FRICTION settings where the jewel itself is cracked or broken...can the jewels be replaced or burnished in these settings using the aforementioned combination tools?...also, would I require a set of friction jewel chucks or could I use the small ww collets I have w/my 8mm Derby lathe..

Hi again Jim!

I was in a hurry when I composed my previous reply, and unfortunately, I'm in a hurry again now, but I'll do my best to offer you a better explanation!

The advice I attempted to provide above WAS about how to re-use gold jewel settings. Obviously, it's necessary to first remove the entire setting from the plate, then remove the jewel from the bezel in the manner described above. Once the broken jewel is removed, the burnished part of the bezel is opened to receive the new jewel, then the new jewel is inserted and burnished into place.

Gold is among the most malleable of all metals, but like anything else, it won't bend and deform indefinitely without cracking and breaking. That being the case, a gold jewel bezel can typically be opened and closed once, maybe twice, but any more than that becomes very dubious.

I wouldn't recommend "learning" on a jewel setting that really matters. I'd first practice on a few that are from scrap plates, etc., and get the hang of it. Of course, like I said above, there's no use trying to replace any jewels without first having a good assortment of replacements. Regardless of how badly a jewel is broken, it's bound to be better than an empty hole in a setting!

Lathe collets will work fine for holding jewel settings, as will regular jewel chucks, most of which fit into a standard #50 lathe collet. The advantage to jewel chucks is that they have a depth stop, which prevents the the jewel from falling down into the center of the chuck. The disadvantage is that they're typically not very accurate, and may be off center by a few hundredths of a millimeter.

Now, to take a slightly different approach to this, assuming you're talking about gold jewel settings that are held into their holes by friction, again, the info above should be good. In most cases, jewel settings of that type are pressed in from the inside of the plates, and should be pressed out from the outside.

In a few late-model watches, such as Hamilton 992B models, etc., friction jewels are set into friction settings, and then the whole assembly is friction fitted into holes in the watch plates. In older watches, however, the jewels are burnished into their settings, and then the settings are friction fitted, screwed, or burnished into their holes in the plates.

Again, I hope this helps, but if it doesn't, keep asking questions, and sooner or later, I'm bound to write something that's relevant!

======================

SM

...thanks Steve...as soon as I acquire the right tooling I'll practice, practice, practice...many thanks again for sharing your knowledge...Jim