3M 03992 Arbor Mount Sanding Disc Power

8-inch medium-grade sanding disc

This 3M arbor-mount disc measures 8 inches in diameter and carries a medium-grade aluminum-oxide abrasive on a non-woven fiber backing. The open-coat construction resists loading while the maroon colour identifies the grade at a glance. It mounts on a 1/2-inch unthreaded hole and is rated for 3,000 RPM maximum operating speed. The High Strength Disc series is built for consistent material removal on metal and composite surfaces.

General metal-finishing and deburring tasks

The medium grit suits weld blending, surface preparation and light stock removal where a balanced cut and finish are required. It is not intended for heavy grinding, precision polishing or aggressive coating stripping that demand coarser or finer grades respectively. Users needing a threaded arbor or a different diameter should select an alternative disc.

1/2-inch unthreaded arbor hole

The disc fits only spindles or adapters with a plain 1/2-inch bore; no threads are present on the disc itself. Verify that your sander or grinder accepts this mounting style before purchase, as an incorrect fit will prevent safe operation.