@ mwolf, I have carved several lithos using cast acrylic and never had the material glob up on me. I would either say you do not have "Cast" acrylic or maybe your tool is really dull. My last litho had lines in it because the carving tool was getting dull but it did'nt glob up at all and I was using cast acrylic. You may want to contact who you purchased it from to make sure they sold you cast and not just plain extruded acrylic material.
CarverJerry
ver. 1.188 Win 7- 64b with 6 GB ram @ 2.8Ghz and dual 1Tb hard drives. Rock Chuck & Ringneck vacuum system hooked up to a Harbor Freight large vacuum. Center line text, conforming vectors.