Rusted tacks and canvas

There is a painting on canvans by Lucio Fontana, done in 1954. The
artist did several holes and cuts on the canvas. The problem is that
the tacks that holds the canvas to the frame are rusty and the
textile fibre around them is oxidized and torn. I have the necessity
to remove the tacks and strengthen the fiber at the edge of the
canvas. In a different situation I would do a strip line but in this
case I can't restretched the painting on the frame because of the
holes and cuts.

I'm open to suggestions in special way from anybody who did specific
studies on paintings with deteriorated canvas that can not be reline
or restretched.

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                  Conservation DistList Instance 12:72
                   Distributed: Monday, March 8, 1999
                       Message Id: cdl-12-72-009
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