Originally Posted by Chas Russell

I cut or scrape away the glassine coating on paper tubes to get to the rougher paper to aid in the adhesive soaking in. I score the glassine slightly wider than the fin and the fillet covers the bare area. Another technique is the in method. Use a pin, drill bit, or knife blade to put small holes along the fin mounting line. I also carefully poke holes or score the balsa fins for adhesive absorption. On plywood fins I use a razor saw to cut lines in the root area to increase the area to glue.

Chas