Klettke wrote:
I have some older Plexi aircraft windows where the paper protection has been
on for a very long time. Some of the paper has shrunk and cracked into
strips, but is stuck well onto the plexi.
I tried water to soften it, but to no avail.
Any suggestions?


Call the manufacturer and ask for hints.

When installing windows in a bonanza, the glass manufacturer suggested
alcohol to clean up the proseal mess. With that said, AC 43.13 and other
sources suggest not to use alcohol to clean them.

http://www.ridoutplastics.com/acplas.html
Gives a lot of information of how different chemicals affect plexiglass.
Ethyl Alcohol appears good. A bottle of Jack and a little time, you
might have your problems solved.

Mineral Spirits isn't real good according to the list. Neither is
turpentine.

Again, the best bet is to call any manufacturer of plexiglass products
and ask them how to get the paper off.

Good Luck,

Dave