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 82238, Scotch-Weld Epoxy Adhesive 420, Off-White, Part B, 5 Gallon Drum(Pail), 7100001145
3M 19674, Scotch-Seal Industrial Sealant 800, Reddish Brown, 5 oz Tube, 7000000792, 36/Case
3M 01000, Scotch-Weld EPX 1:1/2:1 Plunger for EPX Plus II Applicator, 48.5 mL/50 mL, 7010415317
3M 20903, PSA Cloth Disc 348D, P240 X-weight, 2 in x NH, Die 200P, 7000118877
Dynabrade 90872 2" Dia. Coarse NWN DynaBrite Locking-Type Disc, 25/pack
3M 87179, Scotch-Weld Epoxy Adhesive 2216NS, Tan, Part B, 5 Gallon Drum (Pail), 7010309882
3M™ 17323, Versaflo™ Respiratory Helmet Assembly M-407, with Premium Visor and Flame Resistant Shroud, 7000002395, 1 EA/Case
3M 02960, Scotch-Brite Cut and Polish Wheel, CP-WL, 5A Fine, 6 in x 1 in x 1 in, 7100009186, Box of 3
3M 77559, Cubitron II Hookit Cloth Disc 784F, 77559, 36+ to 120+, 5 in x NH, Die 500X, 7100232738 
