Weatherproof varnish for oil paintings

I am a painting conservator working in a London studio.  We have
been asked to treat a small series of decorative oil paintings
(transferred from oak panel to silk and plywood) which will be
outside, unprotected, on two separate occasions later in the year.
We would be interested in any ideas on the best varnish system to
use, to offer protection in case of rain.  The surface coating
needn't be a long-term solution, since the paintings will not be
exposed in this way in the future, but must at least be reversible
after 3-4 months.  We are considering Paraloid B72, perhaps with an
additional waxy coating.


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                  Conservation DistList Instance 15:56
                Distributed: Thursday, February 14, 2002
                       Message Id: cdl-15-56-017
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