I had good luck using a quarter round bit on my router to round off the last piece of coaming on a CLC S&G. Before gluing on the final piece, I anchored a router upside down and ran the coaming cut-out against it. On the top, both sides were rounded over, on the bottom, only the outside edge (i.e., the inside, bottom edge was left square). Given my amateur routing skills, I had to do some touch up sanding, but overall, it made a uniform round-over and looks quite nice.