Cleaning posters

I recently received a question from a colleague who was looking for
a simple, cost-effective solution to the cleaning of some items. The
situation is this: this person has come across some hand-painted
brewery posters on canvas. They were saved out of an old house where
they had been mounted on the walls with staples.  They were walled
over at some point and they are now very dirty.  They probably are
not of great value, but my colleague would like to clean them and
then frame them.  Any ideas on the best approach?  They appear to be
in very good condition other than the dirt.  The individual is
definitely looking for a homegrown (read: cost-effective) solution;
they estimate that the items can't be worth more than a couple of
hundred dollars, but they do have sentimental value since they were
in the house where this individual was born.  Some specifics...

    *   They're from a defunct brewery and probably date somewhere
        between 1900-1920.

    *   They are large, anywhere from 2' x 3' to 3' x 8'.  (He has
        several pieces, so  tests can be conducted on scraps.)

    *   He knows very little about painting, but judges them to be
        oils on canvas.

    *   They are obviously quite sturdy because they've been stapled
        on a wall, torn down, and rolled up and they still look
        pretty good, except for the obvious dirt.

Any suggestions on how to proceed on cleaning?  My gut instinct is
to start with simple water, but what is the best method to apply it
and then clean?  My coworker would appreciate any input or guidance.
Thanks in advance,

Lee Dirks
Microsoft Archives
One Microsoft Way
Building 13/1211
Redmond, WA  98052
206-703-6866

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                  Conservation DistList Instance 10:15
                  Distributed: Friday, August 2, 1996
                       Message Id: cdl-10-15-011
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