From: atm{at}misterg.fsnet.co.uk (Andy Gray)
To: 
Reply-To: atm{at}misterg.fsnet.co.uk (Andy Gray)


On Sun, 4 May 2003 23:19:03 -0700,  "Mel Bartels"
 wrote:


>Are there any modern adhesives that match particular coefficient of
>expansions with commonly used glass (plate, pyrex, whatever), that if used
>with precision ground surfaces to mate, would result in a bond that would
>not distort the glass and that could survive aluminizing and the vagaries of
>time?
>

Anything wrong with epoxy?

It's vacuum compatible (I believe some can even be vacuum baked to a
limited extent); can be flowed into joints if the work is warmed, and is
available in flexible versions if there are any concerns about differential
expansion.

It goes without saying that the joints should be close fitting and
extremely well prepared - it should be possible to get a glue line a few
10s of microns. If this is achieved, the thermal and mechanical effects
must be tiny, mustn't they?

Apologies if I'm going over old ground.

We used to mark glass with an epoxy based ink (Dexter Hysol) that had a
liquid primer based on some sort of silane compound.

Have a browse around:

http://www.henkel.com/int_henkel/loctite_epoxy/index.cfm?&pageid=158&layout=2

for more types of epoxy than you ever knew you needed.

Andy

(Still wrestling with a 1.5" diagonal flat)

Andy Gray, N. Wales, UK.

--- BBBS/NT v4.00 MP