There is a specialized roller for epoxy work. It's a plastic core covered with a very short, stiff bristled nylon which absorbs virtually no resin and is fairly hard. I find it excellent for smoothing out lines in resin I've spread with an auto body putty spreader or plaster knife, or for making sure the resin has totally saturated the FG tape. They are usually available only in a large size, but can easily be hacksawed into the 3"-4" lengths I prefer. A full-sized roller, cut to those lengths, usally gets me thru a boat - cost about $4.00 Cdn. Try your local Fg supply store - would gladly send you the brand name, but mine at stored up at the cabin for the winter.