The Norton A275 NorGrip open-coat vacuum abrasive disc attaches to a vacuum system that clears chips and dust away from the workpiece and sander operator without interruption. The open-coat construction helps prevent clogging. This disc is used for preparing primed and painted surfaces, sanding plastics and fiberglass, and bare wood sanding.
In coated abrasives, the individual abrasive grains are spaced at a predetermined distance from one another. An open coat covers about 50 to 70 percent of the coated surface with abrasive, for greater flexibility and resistance to clogging than a closed coat, which has 100 percent grain coverage. An open coat allows for longer usage time by clogging less, while a closed coat offers a finer surface finish than an equivalent open-coat abrasive. This disc is open-coat. High strength, fiber-reinforced B weight (paper is classified from A to F weight, F being the heaviest and least flexible) is strong – this strength means reduced edge wear during use. This disc is suitable for use with a die grinder or orbital sander. Use with molded rubber back-up pads on a grinder, choosing a hard pad for aggressive cutting, a medium pad for general purpose applications, or a soft pad for contours and fine finishing work. Or, with a random orbital sander, choose a foam back-up pad to match the application. Foam pads can come in different combinations of shape and density for finer or more aggressive work. For example, choose a low profile for uniform contact with the work surface or a tapered edge for small contours or inside corners, choose soft density for 320 grit and finer sanding and medium density for grits coarser than 320.
This has five vacuum holes. Ensure that the holes on the disc are lined up with the holes on the backing pad, in order to properly draw the debris and dust away from the workpiece.
Aluminum oxide is a widely used and versatile abrasive material. It is a tough, fracture- and wear-resistant grit that works well with a broad range of materials, from metals to wood. Aluminum oxide is more durable than silicon carbide and often used for material removal and finishing. P-graded abrasive grains are held to a closer tolerance than non-P-graded abrasives, which means that they offer a more consistent surface finish.
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. Abrasives, because they use many small cutting particles, provide more controlled material removal and better surface finish than cutting tools like end mills and saws, but do not operate as quickly.
Norton Abrasives manufactures a wide variety of sanding, grinding, 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.