Hole-Saw Drum Sander
Sanding the inside of a hole or curved surface can be difficult. To simplify that task, insert a 1/4 x 3-in. bolt into the pilot hole of a hole-saw cutout. Secure the bolt with a washer and nut. Using a hacksaw, cut a 1/4-in. deep slot in line with the bolt. Cut a piece of adhesive-backed sandpaper so that you can slide one end into the slot, wrap it around the cutout, and slide the other end back into the slot. Chuck the bolt into a drill, and you now have a homemade drum sander.