Hi,
as we all know paper on top of platen below T shirt and another one on top of sublimation paper will keep the press clean. I was tired one day though of throwing so much paper / approximately 5 cents per sheet/ . So i decided to put aluminum foil below the T shirt.
Oh, yeah. That worked. Cheaper and most of all will last days. The best thing is you will not need to change it on every shirt. The sublimation ink simply does not stick to it at all. all is much cleaner now and easier to slide the T shirts on and off. Saves a lot of time.
It stays all the time on my lower platens, even when sublimating aluminum business cards and alu plates. And it sticks very well to the spongy silicone.
Hope that helps.