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DeWalt DW8306 4-1/2 in. Type 29 Zirconia Flap Disc (40 Grit) Review (2026)

By The DIYPicks Team ยท Updated July 2026

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4.8$6About $6 each; also in 40-grit and 60-grit versionsCheck Price on Amazon โ†’

The finishing disc that bridges grinding and sanding: zirconia flaps blend welds, deburr edges and knock down surfaces in one pass, leaving a cleaner result than a grinding wheel.

Pros

  • Zirconia flaps blend welds and strip finish while leaving a smoother, more controlled surface than a grinding wheel
  • Type 29 angled backing gives a natural 15 to 25 degree work angle for edge work and blending
  • Self-sharpening cloth removes material fast and lasts far longer than resin fiber sanding discs

Cons

  • Removes metal more slowly than a dedicated 1/4 in grinding wheel on heavy weld beads
  • 40-grit leaves scratches that need a finer disc or sandpaper before paint or polish
  • Flaps wear unevenly and shed if you dig the edge in, shortening disc life

Specifications

TypeType 29 (angled) flap disc
Diameter4-1/2 in
Grit40 (coarse)
Arbor7/8 in
MaterialZirconia alumina cloth
Best forBlending welds and finishing metal in one step without gouging

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