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 bevel bulges outward in a gentle curve from spine to edge, rather than running flat. That extra steel directly behind the edge makes a convex grind notably strong and resistant to chipping, while the curved geometry helps food release and lets the blade glide through dense ingredients with less wedging than a flat grind.

The strength comes at the cost of ultimate thinness and ease of maintenance. A convex edge has more metal behind it, so it is not quite as effortlessly keen as a thinly flat-ground edge, and it is harder to sharpen freehand — holding the curve takes a stropping technique or a deliberate hand rather than a single fixed angle. The reward is an exceptionally tough, smooth-cutting 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.

A traditional Solingen grind — also called a kettle or kessel bulge grind — in which the blade is hollowed high on the side so its thickest point sits a little below the spine rather than at it. Below that bulge the steel is taken down to an extremely thin, finely convexed cutting edge, combining the rigidity of a thick upper blade with the keenness of a very thin one.

The Walkschliff is among the most demanding grinds to execute, historically reserved for the finest German knives and requiring years of a grinder's experience to do well. For the buyer it is a high-craft European alternative to the thin flat grinds of Japanese knives — strong, stable, and keen — but it is a hand-ground specialism, and a knife that carries it is priced for the skill it took to make.