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).

Dynabrade 51624 .1 hp Straight-Line Pencil Grinder, Central Vacuum, 35,000 RPM, 3mm Collet
Dynabrade 95746 3/8" NPT Speed Regulator
3M 71358, 641WY 1/4" X 24", 600 Mesh Diamond Cloth Belt, 7010534894
3M 19677, Scotch-Seal Industrial Sealant 800, Reddish Brown, 1 Gallon Drum, 7000000793, 4/Case
Dynabrade 51810 .1 hp Straight-Line Pencil Grinder, Rear Exhaust, 1000,000 RPM, 1/8" Collet
Dynabrade 51702 .1 hp Straight-Line Pencil Grinder, Rear Exhaust, 60,000 RPM, 3/32" Collet
3M 62818, Adhesive Sealant 760 UV, Black, 600 mL Sausage Pack, 7000121496, 12/Case
3M 84648, Scotch Clear Glue in 2-way Applicator, 6050, 1.6 oz, 7000052506
3M 40466, VentureClad Plus Insulation Jacketing Tape Embossed 1579GCW-E, Natural, 30 in x 25 yd, 7100214292
3M 22409, Roloc Disc 361F, P120 XF-weight, TR, 1-1/2 in, Die R150S, 7000045103
3M 36933, Scotch High Performance Repair Glue in Precision Applicator, ADH669,1.25 fl oz (37 mL), 7010311877
3M 29611, 641WY 1/4" X 24", 100 Mesh Diamond Cloth Belt, 7010534832
Norton 66254432925 Wheel, 3" X 1/2" X 1/4" Bear-Tex, Rapid Blend, Non-Woven 5 Density, A/O, M Grit, 20 Each
3M 11411, Roloc Disc 361F, 50 YF-weight, TR, 1 in, Die R100N, 7000045095 
