Stretching canvas

I manage a picture frame shop and recently been investigating proper
methodology for securing a canvas to stretcher bars. I understand
that many old paintings are lined, then it is the lining is
typically stapled. In these cases, we would simply refer the client
to a conservator.

My concern is for new/recent canvases for the benefit of future
conservators. I questioned a conservator about my concern regarding
staples severing the threads that compose the canvas. I suggested
perhaps using noncorroding thumb tacks (figuring these would pass
between the threads), but he said he preferred staples and he didn't
have any experience with thumb tacks (which he thought might not be
strong enough) but that he sometimes used zinc tacks inserted with a
hammer.

Is there a generally accepted non-invasive securing method?

My other concern was with the acids in the stretcher bars
themselves. Is sealing the bars with gesso (acrylic with calcium
carbonate/titanium dioxide) a satisfactory method of sealing or is
something else recommended?

I'd like to pass on an answer to the 600+ members of the
Professional Picture Framers Online Exchange. Thank you,

Andrew T. Lenz, Jr.
Vice-President
Lenz Arts, Inc.
142 River Street
Santa Cruz, CA 95060
831-423-1935
Fax: 831-423-6840


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                  Conservation DistList Instance 14:5
                   Distributed: Monday, July 17, 2000
                        Message Id: cdl-14-5-014
                                  ***