I'm okay on the buildup using cut up mouse pads, but the area way outside any image has plastic ribs that catch the outside edges of the press.
I wasn't using anything on top since I didn't notice the melting right away, but I have a thin teflon sheet that would cover everything, I don't suppose just that teflon layer would be enough, right? I need to come up with something to cover the plastic ribs that is not so thick as to now allow the press to do the job on the transfers.