- 12/3/18
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A gen bezel will not work in an old BP with the wire clip without some significant modification. The problem is the old BP has a crystal retaining ring built into the case that is not gen-spec. It is actually molded together with the rehaut, a sloped extension surrounding it. This creates a very short step inside the slope for a crystal gasket to sit and the proprietary gasket used is less than 1.0mm tall.Hi this is great post, I was wondering is anyone has the dimension of the bezel on a gen 16710, as in width the and height the of the case section, and the bezel and spring assembly. I have one of the newer BP 16710 which as the crappy old bezel metal wire spring set up, and was wondering if maybe having a play and using a complete bezel ring, insert and spring assembly from WSO would actually fit. Rather than just buying on a whim If anybody knows the gen spec sizes and they are close to the dims on the BP I might give it a go. I suspect they are way off or that the crystal will need changing, but this is more for the want of trying really as the new case I have isnt all that bad CG's look ok and even the over emphasised chamfers are way less, and with a little grey scotch pad work they are far less visible unless under a loupe.
TIA
So that sloped extension would have to be removed with a lathe. Getting the remaining outside diameter of the rehaut right would be crucial, as it would then take a gen-spec gasket to seat the crystal over which a gen-spec retaining ring could be pressed.
But then another issue is that many of these BP 16710s used non gen-spec crystals with a straight edge profile, not a stair-step edge profile. These crystals have a 30.5mm OD so the rehaut opening is about 31.5mm to accommodate the gasket width. A gen-spec crystal OD is 29.5mm at the bottom step where the gasket fits.
So you either need to use two gaskets wedged in together, or drool a bead of epoxy into the gap between the outer side of the gasket and the inner side of the built in retaining ring. I've done it both ways, they both work but are rather tedious and painstaking. A second gasket needs to be shaved vertically to a height matching the stock gasket. And getting epoxy into that tight a space neatly and cleanly presents it own challenges.
Two gaskets
Epoxy drool
Neither one shows appreciably when the insert is in place.
Given these issues, it really makes more sense to just start with a more gen-like case if you want to Franken, though I have seen this done in some rare examples.
Starting with a BP 16750 is simpler as it doesn't have the sloped retaining ring molded next to the rehaut, though when adding a gen-spec retaining ring there is a gap. The gap can be filled with epoxy but then the crystal and gasket have to be installed (or changed) last as the retaining ring is epoxied to the case.
You set the crystal on top of the rehaut ledge then wedge the gasket in around it inside the retaining ring. Or you can set the gasket first and press the crystal down inside it. A little unconventional but it works.
16750 case with rotating bezel
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