Grinding and Sharpening MagnaCut: Belt Recommendations & Technique

MagnaCut is one of the more demanding steels to grind on a 2×72 platform. Its heavy carbide load, the same chemistry that gives it excellent toughness and wear resistance, also means it dulls and loads abrasive belts faster than simple steels like AEB-L or 52100. Most makers report going through roughly double the belts compared to easier stainless steels, so it pays to know what actually works before you start profiling a blank.

Belt Selection

Ceramic belts are the clear choice for stock removal on MagnaCut. They hold their cut rate far longer than zirconia or aluminum oxide belts when working hard, high-carbide steel, even though they cost more up front. Experienced MagnaCut grinders consistently point to VSM ceramic belts (880, 885, or XK870 series) as a strong freehand option, generally outperforming aggressive belts like 3M Cubitron 984F in freehand work, since those need very high speed and heavy pressure to perform well and are better suited to automated grinding setups.

Grit Progression

Start coarser than you might expect: 50 grit is a better starting point than 36 grit for freehand profiling, since it holds an aggressive edge longer under lighter, controlled pressure. A practical progression after heat treat looks like:

Some makers pre-grind bevels at 50 grit before heat treating, then do final finish work afterward, which spreads the belt wear across two easier grinding sessions instead of one long push on fully hardened steel.

Technique

Run higher belt speed with short, light passes rather than trying to force material off with heavy, slow strokes. MagnaCut tends to clump and load belts quickly, so keep a belt eraser or dressing stick within reach and clean the belt often rather than waiting until it feels dull. A generous coolant mister is worth running throughout the grind, both to prevent overheating the edge and to help keep the belt from loading up with swarf.

Sharpening

Once MagnaCut is heat treated to typical working hardness, standard aluminum oxide stones struggle to cut its carbides efficiently. Diamond or CBN sharpening stones and strops are strongly recommended for maintaining a MagnaCut edge; they cut through the carbide structure cleanly instead of just burnishing over it, and hold up far longer than conventional abrasives when used regularly on this steel.