If choosing a knife is anything like dating, then considering the blade grind is like getting to know their parents–you often don't until it's too late. Want to know what makes a kitchen knife cut so differently from a pocket knife? Or maybe you just don't know what the h*ck a full flat grind is and why it's all the rage. Either way, you've come to the right spot to get answers, stat.
Blade grind describes the shape of the blade cross section. Though much less obvious than other characteristics such as blade shape or size, blade grind critically determines the core function and performance of a knife. It will be helpful throughout this section to be aware of some common terminology:
- Primary grind: Also called the “primary bevel”, this is often what people are talking about when they refer to the “grind” of a knife. Some knives may have only the primary grind, while others may have multiple other bevels. However, by definition, every knife has a primary grind.
- Secondary grind: Also called the “secondary bevel”, this is what is often termed the “edge” of the knife. Notice the presence of a secondary grind in the diagrams depicting the flat, hollow, and compound grinds above.
- Full grind: A knife is considered to have a full grind if the primary bevel extends all the way to the spine, as you see in the convex and flat grind diagrams above.
- Sabre grind: Identifies when the primary grind does not extend all the way to the spine. Instead, there will be a flat bevel above the primary grind, as seen in the scandi, hollow, compound, and chisel grind diagrams above.
Closely related to the type of grind, these characteristics greatly affect blade performance:
- Grind height: How much of the blade is shaped; even the grind height between different full or sabre grinds can vary widely, depending on the width of the blade. Grind height has a major effect on how steep the grind angle will be, and therefore the strength, flexibility, and sharpening characteristics of the knife. In the images above, the flat and convex grinds are shown as full, while the scandi, hollow, compound, and chisel grinds are shown as sabre grinds.
- Spine thickness: This affects the feel and hardiness of a knife just as much as the grind. Spine thickness can make all the difference between a hefty bush knife and slicey chef’s knife.
Take a look at the grind type graphics above if you want proof that we’re talking about blade cross-sections, and not your dancing style at the senior prom.
As a flat grind is neither hollow nor convex, it is commonly built to be a jack of all trades. This is a general use grind that excels at cutting apples, whittling and general EDC and kitchen tasks. A “zero-grind” knife is a flat grind without a secondary bevel. The WE Banter and Civivi Baby Banter are great examples of knives with a flat grind blade.
Beloved by the bushcraft community, the Scandi or “Scandinavian” grind excels at wood carving and camp tasks. Notice that a Scandi takes up less than half the width of the blade, and has no secondary bevel at the edge (i.e. a zero-grind). The mass behind the edge creates a thin and strong tool for splitting, feather sticking, and detail work. Frequent stropping is required to keep a scandi (or any zero-grind) sharp, since using a traditional sharpener will create a secondary bevel.
A widely used grind that is a strong all-around cutter, shaver, carver, whittler and slicer. Hollow grinds may have a deep or shallow concave. The hollowness of the blade helps it not stick to the material as it slices. These are not the most durable, as the edges are more prone to chipping or rolling, so they will generally require more maintenance.
One side is ground and the other is flat. Useful for woodworking. Some kitchen knives are chisel-ground to separate slices of food when they’re chopped. Bring on the sushi!