I was working on a project this weekend that involved laminating a 16.5" x 25" piece of matboard. I am using the type of film that does not have the perforation holes, so I hand applied them with a Seal Perforator. This worked fine, but in a couple of places on the finished item, I can still see the little holes. My drymount press was set at the recommended 225 degrees and I left it in for the recomended 4 minutes. Any ideas? Thanks!