
Heat Treating Knife Steel: Complete Guide
Heat treating is what turns a piece of flat bar stock into a functional knife blade. Done correctly, it transforms the steel’s internal crystal structure…

Abrasives
Belt recommendations, grit progression, and warping/heat tips for grinding AEB-L kitchen knives on a 2x72 grinder. Free guide from Torus CNC's ForgeBrain.
1 min readWritten by Rich LinvilleFree to read
AEB-L has the opposite reputation of high-carbide steels like MagnaCut or CPM 20CV: instead of loading and dulling belts quickly, its simple, fine-grained chemistry makes it one of the easiest stainless steels to grind. The real challenges with AEB-L are heat management and warping, especially on the thin stock common in kitchen knives.
AEB-L does not demand premium ceramic belts the way high-carbide steels do. Standard ceramic or zirconia belts in the 36-60 grit range cut cleanly and hold up well, making this one of the more budget-friendly steels to grind in terms of belt consumption.

The right approach depends heavily on stock thickness:
Standard stock (1/8 inch and thicker): Profiling before heat treat is generally fine. After heat treat, a common finishing progression is 50 grit, then 120 grit, then Trizact A65 followed by A45, finishing with hand sanding for a polished result.
Thin kitchen-knife stock (around 0.06 inch or thinner): Grind this fully after heat treat, not before. Start with 36-40 grit, which cuts cooler and holds up well on thin cross-sections, then move to 60 grit to remove the scratch pattern before hand sanding.

Thin AEB-L stock has a well-earned reputation for warping when ground before heat treat, which is why most makers do all of their grinding on thin kitchen blades after hardening rather than before. AEB-L also heats up quickly under the belt, so frequent water dips are essential, particularly on thin stock where the entire cross-section can lose hardness fast if it gets too hot.

AEB-L responds very well to standard sharpening stones and does not require diamond or CBN abrasives the way high-carbide steels do. Its fine, clean grain lets it take an exceptionally keen, thin edge with ordinary shop sharpening equipment.

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