I am having trouble with curvature from pressing (with heat) Lexan (by GE). The sheets that I am pressing the Lexan between are curved in one direction, they are made of AL. When I take the Lexan sheets out of the press the Lexan sheets are curved the opposite way. It would be logical to me for the sheets to bend the same way as the AL not the opposite way. (I do not want the sheets to bend at all but before I buy new AL plates I want to make certain that these new plates are going to solve the problem) Any ideas of why this is happening? Am I inducing stresses, releaving stresses, or maybe a compination of both?