Hi. I was hoping that some of you guys who have been using the split mandrel and sandpaper as a flap wheel could give me some help. There doesn't seem to be much written about how to go about it. I found one piece of information that said to fold the sandpaper in half lengthwise and insert it into the slot in the mandrel. But it didn't say how long the strip should be. I started with a strip of sandpaper 1" x 4" and started on the tang of a broken blade for practice. I was using 320 grit, but it didn't really seem to be very aggressive. I put a little more downward pressure on the Dremel and I guess the sandpaper must have wrapped around the tang, because the shaft of the mandrel was bent at a 45 degree angle and vibrating like crazy. I realize (now) that the shaft was too long (1 1/8") which made it easily bent. I had the motor at its lowest rpm (5000) and had a firm grasp on the on heavily taped blade. How long should the sandpaper strip be? How much should protrude from the non-working end? Should it be spiraled around the mandrel before you begin sanding? How much pressure should be used? If you could answer any of these questions and maybe add some words of wisdom from your own experience, I know it would really help me and a few others as well. I plan to cut about 5/8" off the shaft to give it more stability. Thanks guys.

Regards - Walt