"Pete C." wrote in message
.com...

Robert Green wrote:

Yesterday I was about to toss all the Plexi scraps I have because the
paper
backing is stuck on so tight it can't be peeled off. I decided to try
laquer thinner, assuming it was going to melt the plexiglass since they
were
headed for the trash anyway.

I moistened a paper towel with it, place it on the paper backing and a
few
minutes later it had softened the backing enough so that I could peel it
free (with a bit of work - the scraps are probably 25 years old).

The Plexiglas appears to be completely unharmed by the solvent, which
really
surprised me. I thought would cloud it or melt it. I am now going to
try
to figure out the best way to scale up the process to get the backing
off
some very large sheets of 1/4" stuff. If anyone's interested I'll post
the
brand of laquer thinner and the type of Plexiglas it's working on. I
know I
have some Lexan scraps mixed in, so it may only work on certain types of
Plexi.

--
Bobby G.

There is a Chem-Peel product specifically for that purpose that is
available from plastics suppliers. The laquer thinner may not cause
immediately visible damage, it can appear days later.

I looked for that the last time I went through this. Couldn't find it.
Some chemical facial peels at spas showed up in the search. Lots of
differing opinions how to do this, lots of different types of plastic, some
resistance to LT, some not. One hint for large sheets came out of that
search:

"To get the old paper off and even the new in large sheets we use a broom
stick and two strong guys with big fore arms. You start peeling back the
edge of the paper and then wrap it around the broom stick or other stick and
start rolling it. Be carefull not the let it tear. this works great and when
you are all done throw out the stick. We have also added wood clamps on the
end of the stick to make it easier to roll up. We use a chemical called
Bestine it is the best for removing gummy, sticky materials. It is used in
the sign industry."

http://www.practicalmachinist.com/vb...iglass-194671/

Found a post by you from the long ago past, too: (-:

http://www.homegardenguides.com/gard...r-backing.html

Chem-peel - Specifically designed for that purpose and works very well
without harming the plex. I got mine from a plastic supply house,
imagine you'd have to do the same as it was clearly not a consumer
product. Seem to recall it was made by something like "Ogden Labs" in
Utah.

Pete C.

Thanks for your input, Pete.

--
Bobby G.