On 1 Jan 2005 10:31:22 -0800, (brian morse) wrote:

Hi All, I am renovating a wide angle eyepiece system and found that
the cement between one of the achromats had developed many bubbles. I
soaked the lens in acetone for a couple of days and succeeded in
dissolving the old cement. Could anyone tell me what kind of cement to
use to re-attach the two components. I have some Canada Balsam which
is fairly old (about 35 years) but think that there must be something
better to use by now.
Thanks Brian Morse Vancouver.

You can buy some optical cememts from Estonscience in Toronto.
Balsam is not a good choice as it takes too long to cure.
-Rich