I’m looking for a plastic bendable sheet, Polypropylene sheet I think? on Amazon or Home Depot or walmart, that I can use to make resin molds, specifically rounded ones. I’m not sure what mil I should be looking for. for example, I’m making a resin lamp that is mostly round, about the size of a clock, hollow in the middle, which will be made of wood and resin. I need a plastic bendable strip to create the resin mold/barrier. Any suggestions? Thanks.