I have been using convex ground knives more lately and have been surprised by how differently they perform than the normal hollow and flat ground knives. Picking a knife with the right grind for the job can be as important as using the right steel.

Flat ground knives use a “V” shaped primary grind that can be considered the standard type of grind. Flat ground knives are good for making deep cuts into a binding material, such as cardboard or dense foam. However, hollow and convex ground knives are preferred in many tasks.

This is a picture of a classic hollow ground knife, the Dozier Master Skinner. Bob Dozier is one of the masters of the hollow grind. You can see in this picture how the grinds are scooped out. This means the knife is thinner near the edge and then ramps up to the full thickness of the spin. The advantage is that the knife has the thickness at the spine of a larger knife, but that the metal behind the edge is very thin, like a much thinner knife. For shallow cuts this means the knife will perform like a razor blade. The downside is that when making deep cuts, the material encounters the back of the primary grind at a very obtuse angle, making it bind in materials like wood and cardboard.

Convex grinds are rare today, but they are a great all around grind. Convex grinds have no secondary bevel. The grind starts out flat at the spine, but then falls in towards the edge. Think of an axe head and you get the idea. Convex grinds have very little drag once the cutting edge is in the material and are very strong right behind the edge. Convex grinds are great for splitting wood, and chopping.

I used to prefer using hollow ground knives for general utility work, but I have really started to like convex grinds because they are very tough, easy to sharpen, and do not bind in many materials.

Many custom knife makers will make a knife with a convex grind for you, if you request it. My favorite is Bob Dozier. You can find production convex ground knives from Bark River Knife and Tool.