Hex. Socket Head Bolt M4x10 922112-8

For this particular sander, there are only three screws to remove for replacement of the 196905-1 hook-and-loop pad. One is in the center of the pad. You have to pry out a little felt pad from the center of the hook-and-loop to get to the first screw. I wedged a screwdriver into the fins of the cooling fan to hold the pad from turning ... Read more while loosening the screw. With that screw removed, the hook and loop pad together with its backing plate comes right off. Turn the pad over and on its back side and remove the two Phillips head screws to separate the hook and loop pad from the metal backing plate. These two screws also hold the sealed ball bearing in place. These screws are installed with a thread-locking compound, and will probably be damaged by removal. On mine, one screw twisted off and the on other the threads looked partly stripped. Thinking back, it does make sense that they would be installed with some type of thread-locking compound, since sanders do definitely vibrate. While you have the backing plate off, check the sealed ball bearing in the center. On mine the bearing was starting to feel just a little bit rough, so I ordered an new one along with the other parts. Suggestion: Lay out the parts in order immediately after disassembly and take a photo with your cell phone so you can be absolutely certain to get everything back together in the same order. Reassembly is a pretty straightforward reversal of the disassembly process. The bearing is a tight fit. If you don\'t have a press you can use a large vise to press it into the backing plate. if you don\'t have a large enough vise, you can using a socket that matches the outside diameter of the bearing to tap it in very carefully with a hammer. Don\'t hammer directly on the bearing and be sure to keep it lined up straight. Don\'t force it if it starts to go crooked. Back off and start again. Be sure to use some strong Loctite or equivalent on the two screws holding the hook-and-loop pad to the backing plate.