Cut-Off Wheel vs Grinding Wheel vs Flap Disc?
By Nate Sawyer, Editor · Updated July 2026
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DeWalt DW8062 4-1/2 in. Type 1 Metal Cut-Off Wheel
A 4-1/2 in. Type 1 flat cut-off wheel (0.045 in., aluminum oxide) that turns an angle grinder into a fast metal cutter for rod, bolts, and rebar, with a narrow burr-free kerf. Two-ply fiberglass resists shattering, and it handles carbon steel and stainless. It wears fast, is cutting-only and will explode if used flat, and can bind in a deep cut.
| Type | Type 1 (flat) cut-off |
|---|---|
| Diameter | 4-1/2 in |
| Thickness | 0.045 in |
| Arbor | 7/8 in |
| Material | Aluminum oxide, 2-ply fiberglass |
| Best for | Fast, thin cuts in rod, bolts, rebar and sheet steel on an angle grinder |
DeWalt DW8306 4-1/2 in. Type 29 Zirconia Flap Disc (40 Grit)
A 4-1/2 in. Type 29 zirconia flap disc (40 grit) that blends welds and finishes metal in one step, for a smoother result than a grinding wheel. The angled backing gives a natural 15-25 degree work angle, and the self-sharpening cloth outlasts resin fiber discs. It removes metal slower than a grinding wheel, and the 40 grit leaves scratches.
| Type | Type 29 (angled) flap disc |
|---|---|
| Diameter | 4-1/2 in |
| Grit | 40 (coarse) |
| Arbor | 7/8 in |
| Material | Zirconia alumina cloth |
| Best for | Blending welds and finishing metal in one step without gouging |
Our verdict
These are three different tools that happen to share an arbor. A thin cut-off wheel like the DW8062 is only for cutting through metal, and using it flat for grinding is dangerous. A thick Type 27 grinding wheel like the DW4514 removes weld beads and metal fast but leaves a rough, gouged surface. A flap disc like the DW8306 sits between grinding and sanding: it removes material and leaves a smooth, blended finish in one pass. For most DIY metal projects you want all three: cut-off wheel to size the stock, grinding wheel to knock down heavy welds, and a flap disc to blend and finish before paint.