Adhesive for glass

Robert K. MacDowell <macdowell_r [at] mediasoft__net> writes

>Occasionally we are faced with important items of glassware having
>cracks that do not result in actual breakage of the object. We would
>like a good approach to wicking an adhesive into the cracks and
>having it cure slowly (to allow the wicking process time to
>complete).  I am not enthusiastic about the use of epoxy because of
>the risk of yellowing.

In stained glass conservation, we often have cracks that do not
result in separation of the pieces. We call them "runs."  The only
adhesive we have found that is thin enough to infuse into these
cracks is epoxy.  We don't find UV setting glues very useful because
we're dealing with colored glasses and the glues sometimes don't
set. We use Hxtal, and have not seen discoloration problems except
on old batches (from when the glue was a new product and the kinks
were still being worked).  The discoloration was not the expected
yellow, but purple, and this appears to have occurred only in museum
settings--we've never seen it occur under natural lighting
conditions.

Julie L. Sloan
Vice-president, Cummings Studio
PO Box 427, North Adams, MA 01247
413-664-6578
Fax: 413-664-6570

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                  Conservation DistList Instance 12:14
                   Distributed: Friday, July 31, 1998
                       Message Id: cdl-12-14-004
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