Hi, I have just bought a heat press so I can do T-shirts using heat applied vinyl cut through my plotter. Did a trial 2 colour process on some flat samples & it came out beautiful. When I tried it over some heavy seams of a shirt it just didnt quite want to stick down in a couple of spots. Worried about using extra heat or time as it looks like it might mark the vinyl on the seams. Should I use something between the shirt?