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How to open this wristwatch case?


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Hello, all.

I'd like to open up this old Bulova, but it is unclear to me how to do so.  It definitely isn't a screw back.  It also isn't an obvious pry back.  However, in the first photo you can see there is a gash between the lugs where someone at least TRIED to pry it open before.  Is that how this is supposed to open up?  I know there are watches which are sealed except for the front crystal.  Could this be one of those?

Thanks for any help!



 

gash.jpg

side.jpg

rear.jpg

front.jpg

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Is there any writing on the caseback? like 'use key no.xxx' ?

If not then I would try to pry around, starting with a paper cutter inserted but not twisted, just to get the gap big enough so you can get your caseknife in there.

Anilv

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I expect it has a two piece stem, I can clear;y see where you can remove the bezel in your first photo at 6. You will need to get behind the button with something and pull hard, I used to use a pair of these end cutting nippers.

 

46.032__36786.1477014437.jpg

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To me this looks like a simple two piece case. The "gash between the lugs" is actually put there by the case maker to provide a starting point for inserting a case knife. It looks slightly deformed probably due to the use of inappropriate tools being used to open it in the past. This also suggests that the metal is fairly ductile, and given the style and colouring of the case, that it is solid gold rather than plated. I would not be in the least bit surprised if you find it hall marked inside the case back when you get it open.

The split between the case upper and back can be clearly seen extending from each end of the gash and around the edge of the case and through the center of the stem, which means that this is unlikely to be a two piece stem as once the bezel has been removed the movement will simply lift straight out.

If it is very tight try starting with a single edged razor blade pushed into the split between the two case halves. Just push it in, don't twist. This will hopefully open the gash enough to allow a case knife to do the rest. Whatever you do though take great care not to slip and slice you fingers, and bear in mind that if I'm right about the gold, it will mark quite easily.

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Thanks everyone for your replies.  Sadly, this is just a 10K rolled gold case (still waiting for my first solid gold watch...).  The little groove is indeed where my case knife pretty easily popped off the bezel.  I don't really see how it stays together, actually!  Anyway, here's a photo of the guts.  Seems to be a nice movement, based on the number of adjustments at the factory.  The case is "waterproof" but the rubber O-ring has hardened like a rock and fragmented.  It's unclear to me how it goes over/under the stem, and the stem itself has no groove for an O-ring, so hard to imagine this would actually keep much water out.  But not planning to go swimming with it!  :lol:

10BP movement.jpg

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