Dear Jim,
At 10:23 AM 3/12/2010, Jim Felder wrote:
>would like to repair bridge the gap with some of that window defroster
>repair stuff that everybody talks about.

A flexible-circuit repair pen would be better.  It's
silver-based.  The copper-based defroster-repair stuff is meant to
repair heating elements and has a higher resistance
accordingly.  Check sources at
<http://www.google.com/search?q=flex+circuit+repair+pen>  Chemtronics
is a highly reputable brand, incidentally.

>  But, before I do, I need to
>reattach several inched of loose copper that burned away from the
>mylar backing as well as tidy up a few other places where the laminate
>has rolled back at the edges.

For the loose edges, the first thing I'd try would be a household
iron set to polyester, lots of pressure (use iron edge) and stay on
it a good while.  If that didn't give great results, see below on tape:

>Superglue would probably do a great job in the short run, but it would
>probably not stay attached to the mylar. Any ideas of what to use for
>this repair? Thin double stick tape?

Take a look at
<http://www.tapecase.com/c.148.1.1/double-coated-tape-polyester-film.aspx>.
Clearly whatever adhesive they're using on polyester tapes must stick
to polyester ok.  I'd recommend to check with either 3M or this
outfit's application support people for advice on the best one to
use.  I suspect it will be one of the ones with acrylic
adhesive.  I'd also check with them to see if 3M Super 77 spray
adhesive would be applicable -- it's definitely good stuff, like
everything 3M does.

Yours,
DAvid