If you have an Orbital / DA disk sander with a round pad with holes in it, you know how frustrating and time consuming it can be getting the holes in the sanding disc to match the holes in the pad on the sander. Here is a little quick and easy jig to solve this problem.
Cut a square piece of three quarter inch thick stock to the size of your sander. Take one of your disc and attach it to the block. You can use double sided tape or clamps Using the disc as a pattern, drill at least two three eight inch holes in the block but no more than four. Drill the holes across from each other. Remove the disc. Insert some three eight dowels in the holes. Cut the dowels off about one half inch proud of the block.
To use the jig, place a sanding disc grit side down and over the dowels. Lower your sander over the dowels and press down. Remove the sander and the disc should come with it and the holes will be lined up.
Sometimes the simplest jigs are the best.