Tuesday 27 November 2012

Making a Gold Bezel for a Vintage Omega.

Hello everyone.

Some time ago a customer brought in his old 18ct Omega automatic with a view to getting a new gold bezel for it. He assumed (fairly enough) that it would be a fairly simple matter of ordering the part from Omega. Unfortunately a little research on my part quickly revealed that this was a very unusual, probably hand made, probably Italian, gold case, and there was no way Omega were going to be able to supply any case parts at all. There wasn't even a factory glass listed for it. Some time in the past the original bezel had been lost, and a watchmaker had jury-rigged a repair by mashing an acrylic glass into the case and then clipping a piece of 18ct gold wire around the outside. This makeshift bezel could actually be quite easily removed with a finger nail, and not surprisingly the customer was hoping for something better.


I probably should have said "no I can't help" but sometimes my desire to do what others can't (or just won't) gets the better of me, so I told him I'd have a go. The difficulty was compounded immensely by the fact that the bracelet is hard soldered to the case, so that couldn't come off, and the bezel clips into a groove cut into the case, which being a bit, shall we say 'agricultural' in execution means the tolerances were all over the place. It was never going to be easily to make something fit.

The first thing I did was fire up the lathe and turn up a test bezel out of aluminium, just to test the principle. It wasn't perfect. I did it a bit in a rush (time is money after all) and it came out of the chuck and got a bit mangled at least once. But it did sort of clip in tight enough to convince me it was doable.





The next piece of the puzzle was to go and talk to a jeweller who was able to make a 3D drawing of what I wanted and then print a wax model for me.  (Isn't modern technology a hell of a thing?) Actually he gave me two which is why I still had one to take photos of. I started this project long before I started the blog, so I never took photos of the process. It just spent a long time languishing in what I call my "too hard basket". But I digress. Actually, come to think of it, when I outlined my plan the jeweller raised an eyebrow at me and said he didn't think it would work....   It did.

Anyway, I then took that small piece of wax to Regal Castings up in Mount Eden and they turned it into a VERY EXPENSIVE exact copy cast in 18ct yellow gold. It was at this point that I got my first shock. It cost considerably more than I had calculated, but since I had now just forked over several hundred dollars for it, I was past the point of no return. If I wanted to avoid taking a complete bath on this project then I was going to have to complete it.... Even then it was never going to be profitable... Just educational.... which is why I'm now sitting here typing and trying to make some mileage out of it.



Ok, so I had a lump of gold in the basic shape of the bezel, (which sadly I never thought to photograph) but casting isn't very exact, and I had given generous measurements to make sure I could turn it down to suit. The next part of the process was to put it back in the lathe and make it fit the watch case.... and look nice. This involved turning up various jigs and holders out of alloy so that I could work on it without it flying out of the lathe and getting mangled like my alloy test piece. I started with a chunk of alloy bar stock and once I had done one operation I then modified it for the next operation. As a result I only have the final jig left to photograph for your edification.



I was having a lot of trouble getting the bezel to fit nicely into the groove in the case, let alone clip in place, due to the lack of accuracy in said groove. Around by the crown it was fitting nicely, but the other side wouldn't fit. I tried filing it, and then using a graver around the groove itself to open it up a bit, and eventually just went back to the lathe and turned a bit too much off the piece of the bezel designed to fit inside the groove. Great. It now sat down on the case absolutely beautifully.... It just didn't clip. What to do, what to do?

Hmmm, time to use some lateral thinking. I fitted a piece of stainless steel bar stock in a tool holder in the lathe, brought it in on an angle to the bezel and very carefully turned the bezel by hand so that the stainless acted as a burnisher and very slowly formed the bezel 'clip' so that it splayed outwards. Pretty much the opposite process of making a rubbed over setting to hold a stone in a ring. Mercifully it worked perfectly and I finally had something I could glue a glass into and clip onto the watch.


From my point of view it isn't perfect. If I had to do it again I would make it a little taller to allow a deeper seating for the glass, but really that's just a minor quibble.


I'm happy.
I hope the owner will be too.



3 comments:

  1. Excellent work. What a unique bracelet that watch has. I can see why the owner was interested in keeping and enjoying the Omega

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  2. Thanks.
    I was away when the owner picked it up, but he did make a point of coming back in and telling me how please he was with it. He also told me he had been wearing it while out dinner the previous evening and one of his dinner companions commented on it, which made him doubly pleased.

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  3. It's been a long time since this last blog post - when are you going to post some more?

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