Mounting canvas

Can anyone tell me the harmful effects of mounting an early 19th
Century oil painting on a sheet of Aluminum?  A director at the
local museum said that two well respected framers suggested mounting
the canvas on a piece of aluminum with fixative. The canvas had some
damage and the framers were afraid that restretching the picture
would damage it even further.

This sounds pretty risky to me, but I wanted to know what some of
the experts thought.  I don't think fixative is meant to act as a
long term holding agent and I'm not sure what it could do, over
time, to the oil paints on the opposite side. Thanx,

Amy Rider

                                  ***
                  Conservation DistList Instance 11:24
               Distributed: Thursday, September 11, 1997
                       Message Id: cdl-11-24-015
                                  ***