This assembly allows the 3M Disc Pad Face Plate to be easily changed without removing the disc pad hub, allowing the operator to use a single tool for multiple applications from heavy grinding to finishing a workpiece.
Some face plates have ribbing on the bottom face. Ribbed face plates provide additional force when needed for optimal fracturing of the abrasive mineral. By reducing the area of contact, or pressure per square inch (PSI), ribbed face plates increase the grinding pressure of the abrasive with the same amount of operator effort, and extend disc life when dulling is a problem.
Choose a plate with the level of firmness needed for the application?a lighter density face plate for lighter weight grinding applications, and a harder density face plate for more heavyweight grinding applications. Using the correct face plate for the application ensures that the abrasive mineral will fracture as it should, maximizing the life of the abrasive. The plate comes in one of four different colors that indicate the density so the correct plate can be easily identified in the workroom: red = extra hard (for heavy grinding with the coarsest grades), black = hard (for heavy metal removal, large welds, etc.), gray = medium (for general purpose grinding and finishing), and white = soft (for finishing operations on flat or contoured surfaces).

3M 53038, 663FC, 3/8" X 90", 20u, Diamond Trizact Belt 7100205972
Dynabrade 13509 Dynastraight Finishing Tool, Rear Exhaust, 6,000 RPM, 5/8" (16 mm) or 1" (25 mm) Dia. Arbor
3M 08017, Marine Grade Silicone Sealant, White, 3 oz Tube, 7000120479, 6/Case
Standard Abrasives 725007, Buff and Blend Cross Buff HS, A/O Medium, 1 in x 3/8 in x 2 Ply x 8-32, 7000046828
3M 14750, Scotch-Brite EXL Unitized Wheel, XL-UW, 2S Fine, 3 in x 1/4 in x 3/8 in, 7000000699
Standard Abrasives 725017, Buff and Blend Cross Buff GP, A/O Fine, 3/4 in x 3/8 in x 2 Ply x 8-32, 7010330367
3M 14753, Scotch-Brite EXL Unitized Wheel, XL-UW, 8A Medium, 3 in x 1/4 in x 3/8 in, 7000000700
Standard Abrasives 882141, A/O Unitized Wheel, 821, 3 in x 1/2 in x 3/8 in, 7010367108
3M 03738, Scotch-Brite Cut and Polish Unitized Wheel, CP-UW, 7A Medium, 3 in x 3/4 in x 3/8 in, 7010364917
3M 22397, Roloc Disc 361F, 60 YF-weight, TR, 1-1/2 in x NH, 7000045097 
