I do the paper/glue method too. I put glue on one side of the fin, spread it out, wipe off most of it with my finger, stick on the paper, immediately clamp the fin between 2 smooth boards. After 15 minutes I take it out and do the other side, then put it back between the boards. I let it set for 12 hours. They are almost always smooth and straight. I do it mostly to make the fins strong in the direction perpendicular to grain and it works well for that.I launched it on a B4-4 I think it was? It in the video below if I can get it to post.... But because this was my first time papering fins, I used the glue/water/copy paper method. It worked great just warped the fins slightly.