Since looking into refurbishing my grandfathers watch that was passed on to me I would like to ask the following.

Is there a general consensus as what are the tolerances when we match a bezel with a crystal ?

I will use my current predicament as an example.

After finally figuring out what the correct crystal is for my watch (25-123), the external diameter of this crystal is 294 mm according to the documentation I have found on the Internet (will link this below, is there not a resource here at the forums that this information can go into ??)

https://blog.esslinger.com/wp-conten...tal-number.pdf (used this document to find out the correct crystal for my 9061/0)
Generic Crystals to Fit Rolex® (used this document to get the dimensions, "cyclope 123")
http://www.julesborel.com/Catalogs%2...2010-17-16.pdf (this is just for reference)

Now to the bezel,

I have found the following bezels whose dimensions have been recorded.

These bezels are for a 25-117 crystal that has an external diameter of 295 mm, that is 0.1 mm bigger external diameter than the 294 mm of the 25-123

https://www.chrono-shop.net/en/datej...C3%B834mm.html - 29.35 cm
https://www.chrono-shop.net/en/datej...C3%B834mm.html - 29.32 cm
https://www.chrono-shop.net/en/datej...C3%B834mm.html - 29.30 cm
https://www.chrono-shop.net/en/datej...C3%B834mm.html - 29.24 cm
https://www.chrono-shop.net/en/datej...C3%B834mm.html - 29.24 cm
https://www.chrono-shop.net/en/datej...C3%B834mm.html - 29.18 cm
https://www.chrono-shop.net/en/datej...C3%B834mm.html - 29.04 cm
https://www.chrono-shop.net/en/datej...C3%B834mm.html - 28.20 cm

Such a variation in measured diameters and all these bezels internal diameters are smaller than the crystals exterior diameter.

i.e. best case scenario,

crystal external diameter: 295 mm (or 294 mm in my case)
bezel internal diameter: 293.5 mm

So the question is as follows, are the bezels meant to be slightly smaller, in so that there is a degree of "stretch" that will take place when the bezel is placed over the crystal to form an air tight seal ??

I need to also buy a bezel and as my bezel has a split on one side the measurement ive taken cant be used to choose the 'correct' sized bezel, but posting the pics for reference

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