Sanding Block That's a Perfect Fit
After cutting out an arc with a band saw or jig saw, don't toss out the waste piece. It comes in really handy for making a perfect-sized curved sanding block that you can use to sand the bottom edge of the arc smooth.
Simply cut out a section from the middle of the waste piece (Fig. 1). Then, to turn this piece into a sanding block, attach a strip of self-adhesive sandpaper to the curved edge. The arc on the sanding block is a perfect match to the arc on the workpiece (Fig. 1a).
Online Editor, Workbench