A lot of people confuse the blade grind with talk on the edge grind. The blade grind refers to the side of the blade. Flat Grind is a straight tapered line from the spine to the edge. Sabre is a straight vertical or parallel section down from the spine and then it tapers about 1/4 of the way down the side of the knife to a flat grind to the edge. The Sabre grind therefore is heavier and potentially stronger....although in Bussekin knives a Flat Grind is plenty strong enough for me.

A Convex grind is an appleseed shape curving down from the spine to the edge...or often called tear drop shape...you could take a Sabre Grind and using a loose belt on a sander remove metal from the side to create a Convex grind.

There are others such as a Chisel grind or a Scandi Grind...but the above three are the ones used on Bussekin blades.