Achromatic lens cement

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.

Balsam still works fine and is probably the best replacement in terms of
matching the original performance.

Clear Skies

Chuck Taylor
Do you observe the moon?
Try http://groups.yahoo.com/group/lunar-observing/

Are you interested in understanding optics?
Try http://groups.yahoo.com/group/ATM_Optics_Software/

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"brian morse" wrote in message
om...
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.

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

Edmund has five+ cements...



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.

have some Canada Balsam which
is fairly old (about 35 years) but

Cana Balsam is about as good as it gets but I would like to hear from the
experts associated with this group. To review there are three advantages. 1
softens in hot water. 2. water soluable for easy cleanup. 3.non-dispersive
refractive index.

On 10 Jan 2005 19:34:50 GMT, (HAVRILIAK) wrote:

have some Canada Balsam which
is fairly old (about 35 years) but

Cana Balsam is about as good as it gets but I would like to hear from the
experts associated with this group. To review there are three advantages. 1
softens in hot water. 2. water soluable for easy cleanup. 3.non-dispersive
refractive index.

Canada Balsam is not that great. It tends to yellow, can allow
slippage, especially of a large heavy element because it takes
ages to dry. It's better used as the cement for microscope coverslips
for slides. There are plenty of synthetic cements that are
available.
-Rich

Canada Balsam is what has been the commercial/scientific standard for gluing
optics together for a long time. One of the things that is nice about it is
that it is dissovable so repairs can be made. More modern adhesives (UV
curable adhesives) are a lot more difficult in the regards to repairability
and are not as recommended for large optics due to the lack of flex when in
the joint to be glued together.

--
Why isn't there an Ozone Hole at the NORTH Pole?

Balsam is not a good choice as it takes too long to cure.

I believe Balsam hardens upon cooling because it softens again upon heating
implying that there are no irrevesable reactions taking place.

Just to keep things in perspective, I sent this in about a month ago. I
thought my PC was going nuts because I kept looking for it and it never showed
up.