I made two sanding jigs for radiusing the edges, I drilled a 7/16" hole through a piece of maple boom stick then split in two halves, one for 150 grit, the other for 220. It's about 6" long. I knock the edges off with a Master Airscrew plane then finish the rest with 150 then 220. I color the edge surface with the side of a pencil then sand until the pencil makings disappear.