Ok so I know your not supposed to spray onto silicone mats cause of the reaction with butane...but ok the concentrate is on a small sheet of ptfe laying it directly on the floor of the chamber I notice hot spots ( I have a digital heat pad on the bottom of the chamber) So I thought since I have a round silicone mat that fits the vac chamber perfectly I want to lay the silicone mat on the bottom of the chamber then lay the ptfe sheet with concentrate on top of that. my thinking is the silicone mat will distribute the heat better. does that seem ok? the heat from the pad and the vacume wont do anything to the silicone mat and contaminate things right? I don't see why it cant be done but figured I would ask what some of you guys do? THANKS!!