thin or thick gasket..whats the difference

percolation problems. We talking about a coffee pot Bruce or a gasket. that's what I thought but wanted to know for sure. I am still trying to get in touch with that guy in Dayton on that 904. he has not gotten back with me. I stuck an old 904 that I had laying around behind this 360 and did a few burnouts with it and I think it is slipping some. (junk).