Orbital and Random Orbital Disc Sanders
Examine the sanding disc located on the bottom of the hand sanders. Orbital and random orbital sanders include the motor and power switch on top and are powered by electricity or air. It's time to replace the disc when the grit across the surface is no longer consistent or any time you find a worn spot in the grit that has worked its way down to the paper backing, which not only gives the best performance, but also protects the rubber sanding pad from damage.
Warm the sanding disc to soften the adhesive by running it briefly while keeping the disc in contact with a smooth, sandable surface. Turn off the sander, and unplug it from the power.
Turn the sander over so that the disc is facing up. Lift the disc by its edge, gently working your way around the outer edge of the sanding pad. Peel the disc back until it lifts away from the sanding pad.
Clean any adhesive residue from the face of the sanding pad with a rag dampened in acetone. Allow 5 minutes for the acetone to evaporate before applying a new disc.
Turn the power off, and unplug the sander before checking the disc for wear. Rotary table sanders, frequently called Disc Sanders, are mounted with the motor spindle protruding out horizontally so that the sanding wheel is vertical with the sanding disc mounted on its face. Turn this wheel by hand, and check the sanding disc for signs of wear. Replace it when you see patterns similar to those described for orbital sanders.
Lift the disc from the edge gently, turning the wheel as you work the disc off of the surface. Lift the disk away from the wheel, and slide it out of the opening in the table.
Clean any remaining adhesive from the wheel with a rag dampened in acetone. Allow 5 minutes for the acetone to evaporate before applying a new disc.