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 20967, Portable Utility Cloth Roll 314D, P240 J-weight, 1 in x 20 yd, 7010290604
Standard Abrasives 863110, A/O Unitized Wheel, 631, 2 in x 1/4 in x 1/4 in, 7000144629
Dynabrade 11476 Dynabelter Abrasive Belt Tool, Heavy-Duty
Dynabrade 13509 Dynastraight Finishing Tool, Rear Exhaust, 6,000 RPM, 5/8" (16 mm) or 1" (25 mm) Dia. Arbor
3M 86745, Diamond Disc, 2" Roloc, 674W, 120 Mesh, TR, 7100022116, Box of 10
Dynabrade 10690 Filter/Regulator/Lubricator, FRL40, 1/2" NPTAssy.
Dynabrade 95843 Dynabrade Air Lube 10W/NR, 1 Gallon
3M 05009, Utility Cloth Roll 211K, 100 J-weight, 1 in x 50 yd, Full-flex, 7100016843
3M 33780, 641WY 1/4" X 24", 400 Mesh Diamond Cloth Belt, 7010534915
Dynabrade 15420 Dynafile III Abrasive Belt Tool
Dynabrade 11477 Dynabelter Abrasive Belt Tool, Heavy-Duty
Dynabrade 95544 Gear Grease, 2.5oz. Tube
Dynabrade 96101 Dynabrade Air Lube 10W/NR 24 Per Box
Norton 66254414832 - 3" X 1/4" X 1/4" Vortex Rapid Blend Unified Wheel, 5am U2305, 40 Each
3M 01328, PSA Cloth Disc 348D, P180 X-weight, 3 in x NH, Die 300V, 7000045068 
