Now the chance to really start shaping aluminum. The ends of the spars needs to be rounded with no sharp corners, burrs, or aother nicks that can eventually turn into a crack. I read on another builder's site that he found a socket that had the right radius as the 1/4 inch required radious around the holes at th end ofthe spars. I centered that up on the hole and traced around it. Perfect!
After some file work, rounding more with the grinder and some polishing with the Scotchbrite pad and 400 grit sandpaper, the ends looked good.
A plastic socket tool found in my cheap screwdriver bits had the perfect radius to outline a cut.
Before and after. Raw and nearly completed on the right.
