Acetone seems not to be a very good solvent for plexiglas. I've been using a solvent glue made from methylene chloride that is much more active. It is nasty stuff with long warning labels. There is a "filled" plexiglass glue ont he market that is make from the methylene chloride and already has some disolved plexiglass in it. This is a thicker material. You might try getting this stuff and thinning it. I have found these products at craft stores and as plastics suppliers.

Acetone works very nicely for disolving styrene plastics. It is amazing how much styrene foam can be dissolved in an ounce of acetone, and also how fast it dissolves the stuff. It makes a good magic trick: put a bare 1/8th inch of acetone in the bottom of a mason jar, and then put in some styrene foam, and some more, and some more ...

PGJ