Look to the image how they lay resin look on the sides, also heat protective they heat acetone for couple seconds and more fairy tales i was in love.

From a H&S view, we all know how dangerous the materials are we work with but in my opinion there is not point risking yourself or your workshop by heating an already very unstable liquid!!! Acetone flashpoint is something like -30deg C (from memory) so it's just waiting to go up. I ask the question, would you heat petrol?.... no, so why heat acetone!