Learning a lot now that I have a reliable Knight press. However the trick to Unisub Ultra Gloss sheet stock still alludes me. Following Conde's guidelines at 400 degrees, I tried 60 sec - no luck, 30 sec, 45 sec, 65 sec... Every sample sticks to the metal and will not peel off.
I have no issues with dog tags or any of the plastic type of substrates.