Flat-sand easily with a couple of clipboards
Because small parts are difficult to hold flat against a moving abrasive, it's all too easy to round their edges or grind them to wedges when power-sanding.
Move the part over the sandpaper instead of the other way around. Place two clipboards together as shown above, and clamp a sheet of sandpaper under the clips. Firmly held at both ends, the sandpaper stays smooth as you move the part back and forth to sand it flat.
—Frank Toroney, Glenmoore, Pa.