I am having some print flattening trouble with my 16x20's. I usually use a dry mount press after they have dried on screens but my press is only 12x12 so I have to do 16x20's in sections. My trouble is the top edge of the print "frills" and no amount of pressure etc seems to eliminate it. None of the other edges frill so I am at a loss to explain it. None of my other sizes of prints do this i.e 11x14,8x10 etc. Does anyone out there have a tried and true method?