Flap & Fiber Discs

100+ products

Expected delivery: Wed, Nov 18

Flap discs and resin fiber discs run on angle grinders to remove weld beads, bevel edges, clean up mill scale and blend surfaces before paint. Flap discs are built from overlapping abrasive flaps on a backing plate, so fresh grain is exposed as they wear. Fiber discs are single-layer abrasive on a stiff fiber backing and need a backup pad. This section covers both in common 4-1/2", 5" and 7" sizes, in aluminum oxide, zirconia and ceramic grains, with 5/8"-11 threaded hubs on some styles.

What to check before you order

  • Type 27 or Type 29. Type 27 discs are flat and work at a low angle for blending. Type 29 discs are conical and remove more material at a steeper angle.
  • Grain. Zirconia is a durable choice for steel. Ceramic suits heavy pressure and stainless. Aluminum oxide is economical for light work.
  • Grit. Coarse grits remove beads, and finer grits leave a surface ready for coating.
  • Backing. Fiberglass backings are stiff and common. Some backings can be trimmed down as the flaps wear.
  • Speed and fit. Confirm the arbor or hub and make sure the disc's maximum RPM meets or exceeds your grinder's speed.

Buying guide: Abrasive grit guide: which grit and disc type to use

Common questions

Do fiber discs need a backup pad?

Yes. Resin fiber discs must be mounted on a backup pad of the right size, held with a retaining nut.

Return to abrasives, or compare grinding and cut-off wheels and grinders and sanders.

Flap & Fiber Discs: page 3

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