This assembly allows 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 foot (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 81283, Scotch-Weld High Strength Retaining Compound RT38, Green, 50 mL Bottle, 7010310185, 10/case
3M™ 72787, Calibration Kit 529-04-48, Large, 7000052154, 1 EA/Case
3M 16582, Accuspray Atomizing Head, Blue, 1.2 mm, 7010363219
3M 33780, 641WY 1/4" X 24", 400 Mesh Diamond Cloth Belt, 7010534915
3M 16612, Accuspray Atomizing Head, Orange, 1.4 mm, 7100017731 (4 Nozzles/Kit)
3M 29611, 641WY 1/4" X 24", 100 Mesh Diamond Cloth Belt, 7010534832
3M 21543, Scotch-Brite Roloc Clean and Strip XT Pro Extra Cut Disc, TR, 2 in x NH, A XCS, 7100179815, 60/box
Dynabrade 78291 2" Dia. x 2A M Medium Type R Unitized Locking-Type Disc, 25/pack
Dynabrade 59339 Vacuum Cuff, 1", w/Groove
3M 28217, Cubitron II Roloc Disc 984F, 60+ YF-weight, TR, 3 in, Die R300V, 7010326790
3M 22396, Roloc Disc 361F, 36 YF-weight, TR, 1-1/2 in, Die R150S, 7000045091 
