Norton Charger R822 flap discs are suitable for light stock removal, blending, and finishing on a variety of metals. All Norton fiber discs feature a full resin bonding system with heavy-duty fiber backing for increased strength, durability and tear resistance. With a type 29 flap disc, hold the grinder in operation at an angle between fifteen and twenty five degrees to the work surface. Steeper angles will weaken the flap edges. Coated abrasives have individual abrasive grains spaced at a predetermined distance from one another. This is a closed-coat disc. A closed coat covers 100 percent of the surface with abrasive grains, for more stiffness and better surface finish than an equivalent open coat, where abrasive grit covers 50 to 70 percent of the surface. This disc features a resin bond. Resin bonds have good moisture resistance, are harder and less flexible than glue bonds, and have good heat resistance and grain retention. Resin bonds are useful for abrasive operations with high operating speeds, impact, and sudden loading, as the resin bond is strong and can withstand rough treatment. Use with molded rubber back-up pads, using a hard pad for aggressive cutting, a medium pad for general purpose applications, or a soft pad for contours and fine finishing work. Zirconia alumina is a self-sharpening abrasive that allows for a faster cut rate and longer life than aluminum oxide, due to its ability to fracture and refracture, creating new cutting edges. Zirconia alumina is often used for high stock removal on wood and metals. Abrasives are used for a variety of applications from shaping a part to fine finishing, depending on the grit size. Low grit numbers like 40 are coarse and are used for removing excess material and shaping a part. High grit numbers like 400 are fine and help to create a smooth surface finish. Norton Abrasives manufactures a wide variety of sanding, sanding, and polishing abrasives, and has been located in the United States since 1885. In 1990, Saint-Gobain purchased Norton, keeping its manufacturing facilities and offices in the same location. Norton/Saint-Gobain has been recognized as a Global 100 Sustainable Company, as well as earning ISO 9000 and 14001 certification for quality and environmental management standards.