Flashing and sandpaper team up in the tight spots
Sanding blocks and most portable power sanders don't reach into small spaces well, and hand-sanding in tight spots can wear out your fingers.
Create your own custom-shaped sanding plates from flashing material. With a pair of tin snips, cut the shapes you need from 28-gauge aluminum roof flashing you find at most hardware stores. Attach adhesive-backed sandpaper to the flashing, and trim to size. The rigidity of the flashing enables you to maintain firm pressure, especially when you're sanding in areas where your fingers can't reach.
—William J. Carroll, Dallas, Pa.