Re: 6 size Elgin

You are correct about a friction fit, especially with French clock glass.
But there is no flex or snap fit for a watch crystal or any other glass.
Glass does not flex, except when it breaks.

You are also correct about a metal bezel flexing or expanding when heated,
and contracting when cold. Glass does not flex.

"dAz" <dazb@zipDOTcomDOTau> wrote in message
news:43e6b400$0$10626$afc38c87@xxxxxxxxxxxxxxxxxxxxxxx
The Baron wrote:
I believe we have had this discussion before, glass does not flex and if
you
clamp a bezel too tight it will break the glass. That's why they make
crystal cement, to hold glass in a bezel, without stress to anything.

well in this case it does, the old crystals were very very thin, glue is
not necessary unless the groove in the bezel is damaged, the slight
distortion of the thin bezel when fitted back onto the case is enough to
firmly hold the crystal in place.

I know this because I was shown how fit them by an old guy in his late
80s who ran a watchmakers supplies in Sydney, he had thousands of the
old crystals (this was 30years ago), he after a good 60+ years in the
trade would rarely break a crystal fitting into the case.

the trick is to find a crystal that just snaps in the bezel with very
little effort, and when fitted back onto the case the bezel will clamp
down on the crystal, I have fitted hundreds of hunter crystals this way
and rarely break one or have one fall out, I still have a few crystals
left but all the common sizes are gone so now mainly use the very thin
hunter plexis, and for all intents and purposes looks just like the
originals and don't need a stock of different heights either like I had
to with the older crystals.

the thicker curved openface crystals and the thick round bevelled glass
that go on french clocks are a friction fit too, no glue, just warm the
bezel up till its almost too hot to touch, drop the glass in, the bezel
cools and shrinks holding the glass firmly in place.

fortunately I still have a guy that can hand grind and polish a bevel
edged glass for french clocks, snap fit in, no glue, and hard to pick
from an original except maybe for the colour of the glass


.

Relevant Pages

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  • Re: 6 size Elgin
    ... crystal cement, to hold glass in a bezel, without stress to anything. ... I know this because I was shown how fit them by an old guy in his late 80s who ran a watchmakers supplies in Sydney, he had thousands of the old crystals, he after a good 60+ years in the trade would rarely break a crystal fitting into the case. ... the trick is to find a crystal that just snaps in the bezel with very little effort, and when fitted back onto the case the bezel will clamp down on the crystal, I have fitted hundreds of hunter crystals this way and rarely break one or have one fall out, I still have a few crystals left but all the common sizes are gone so now mainly use the very thin hunter plexis, and for all intents and purposes looks just like the originals and don't need a stock of different heights either like I had to with the older crystals. ...
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