Grind guide

A category covering blades ground with more than one geometry stacked into a single cross-section — typically a convex (or flat) primary bevel at the very edge, with one or more hollows ground higher up the blade face to relieve material behind it. The aim is food release and reduced wedging: the hollow opens an air gap so dense produce breaks away from the blade instead of clinging to it, while the convex steel at the edge keeps the apex strong and the knife driving through the cut.

The named variations in the Modern Cooking catalogue differ in where the hollows sit, how many there are, and whether the two faces are ground alike:

S-Grind — a convex primary bevel at the edge with a hollow ground into both faces just above it. The symmetrical "S"-shaped cross-section is the classic food-release grind: relief above the edge, strength at the edge.

C-Grind — an asymmetric S-grind. Both faces keep the convex primary bevel, but only one face carries the hollow above it. The single-sided relief biases food release to one side, and is simpler to grind and to maintain than a full S.

B-Grind — a stacked twin-hollow grind: a tight, narrow hollow immediately above the edge, with a second, broader and wider hollow above that. The staged relief gives especially strong food release across the height of the blade.

S-Hook Grind — also called a hook, harpoon, or J grind. An S-grind taken to an extreme, with the hollow placed very close to the cutting edge. The aggressive near-edge relief gives outstanding food release, at the price of being the most maintenance-sensitive of the family.

Asymmetrical-B Grind — a B-grind in which the twin-hollow structure is carried on one face while the other is ground differently (or left without the upper hollow), off-setting the edge. It combines the staged food release of a B-grind with the handed, steering character of an asymmetric grind.

In every case the gain is food release and reduced drag, and the shared cost is sharpening: as the edge is thinned over the knife's life, maintenance eventually reaches the hollowed steel, which cannot be flattened on a stone the way a convex or flat bevel can. How soon that happens depends on how deeply the hollows are cut and how close to the edge they sit — exactly what separates a gentle S-grind from an aggressive S-hook. These are high-craft geometries, prized by makers and experienced users for their cutting feel, and best appreciated by a cook who maintains their own edges.

A grind whose faces curve outward in a continuous arc rather than falling in a straight line. The practical consequence is that it has no shoulder — no abrupt step where a bevel meets the blade face. Food release improves for the same reason: a curved face touches the cut surface along a narrow band instead of a full flat plane, so slices break away rather than clinging. Drag behaves differently too. A convex blade carries more steel than a flat grind of the same spine thickness, so it is not the lowest-drag geometry available, but the resistance it does create builds smoothly through the cut instead of arriving all at once as the food meets a bevel transition. The feel is progressive rather than sudden.

The curve also supports the edge. Steel thickens quickly behind the apex, which raises edge stability at a given sharpening angle — the apex is less prone to rolling or chipping under lateral load. How much of that you get depends on where the convexity sits. A face can be curved the whole way from spine to edge, or the curve can be confined to the last millimetre or two as a convex "appleseed" edge on an otherwise flat blade. The first shapes how the knife moves through food; the second is felt almost entirely at the edge.

A grind in which the blade tapers in a straight line from the spine down toward the edge, with no curve or hollow in the bevel. The flat grind is the most common geometry on modern double-bevel kitchen knives because it balances cutting performance and durability: thin enough behind the edge to slice well, with enough steel behind it to stay strong.

A true full flat grind, running from spine to edge, is keen but can wedge in dense produce as the food meets the widening blade; many kitchen knives use a partial flat grind that begins lower on the blade to manage that. The flat grind's appeal is its predictability — it sharpens straightforwardly, behaves consistently, and asks nothing unusual of the user.

A grind with concave bevels, ground into the blade with a curved wheel so the sides scoop inward toward the edge. Removing that steel leaves an exceptionally thin, keen cutting edge and a noticeable air gap behind it, which can aid release on certain foods. The geometry produces a very sharp apex with minimal effort.

That thinness is also the weakness. A hollow-ground edge has little steel supporting it, so it is more prone to rolling or chipping under hard use and loses its bite once sharpening reaches the thicker steel above the hollow. It suits slicing tasks and precision work, and is poorly matched to heavy or careless cutting.

A grind sharpened on one side only — the front face carries the full bevel while the back is flat or very slightly concave (the urasuki). This is the traditional geometry of Japanese trade knives such as the yanagiba, deba, and usuba, and it produces an astonishingly thin, acute edge capable of cuts a double bevel cannot match, along with the characteristic way a single bevel steers through food.

Single-bevel knives demand commitment. They are hand-specific (a right-handed knife is ground for a right-handed user), they steer to one side by design, and they require a particular sharpening method that maintains both the front bevel and the flat back. In skilled hands they are unmatched for precision slicing and clean single-direction cuts; for a cook unwilling to learn their upkeep, they are the wrong tool.

The Kesselscher Walkschliff is a traditional Solingen grind in which each face of the blade curves outward from the spine, reaching its greatest thickness slightly below it before tapering towards the edge. Beneath this pronounced convex “bulge,” the blade is ground exceptionally thin and continues into a fine, subtly convex cutting edge. This distributes material through the upper blade for rigidity and stability while preserving the low cutting resistance of a very thin edge.

Achieving this compound geometry consistently demands considerable control, specialist knowledge and experience, whether it is produced on a traditional grinding wheel or with a belt grinder. Once part of Solingen’s celebrated grinding tradition, the Walkschliff is now practised by relatively few makers. A well-executed example is valued for the way it reconciles qualities that can otherwise seem opposed: strength through the body of the blade, fineness behind the edge and an exceptionally keen, confident cut.