Blade Grinding and Blade Geometry knifeopedia
By applying different ways of grinding, various blade geometries can be produced:
Hollow grind
The cheapest way of grinding a blade. The blanked steel is just ground in the lower area. Typical way of grinding for very low end knives, but also for serrated edges.
PROS
Inexpensive
CONS
Thick blade above grinding area = high cutting resistance
A lot of cutting drag in area of concave edge
Thin and fragile blade on cutting edge

Flat grind
The blade is ground flat on both sides to a thin edge.
PROS
Thin blade and potentially good sharpness
CONS
Thin and fragile edge
Contact of food along the entire blade = sticking and drag; more power needed for cutting

Convex grind
The blade is ground on both sides with a convex geometry. Common way of grinding German style knives.
PROS
Food contact only on small area of blade = less sticking and drag
CONS
Thicker blade in area close to edge = less sharpness




Single bevel flat grind
Adding a flat bevel on one side of the blade. Common way of grinding for scissors, but not knives. Also found in cheaper look-alikes of traditional Japanese knives.
PROS
Very inexpensive way of blade grinding
CONS
Blade only works for either left- or right-handed people, not for both
Straight cuts are difficult
Single bevel hollow grind
Hollow-grinding of blade on one side, and adding a bevel from the other side. Way of grinding of traditional Japanese single bevel edge knives.
PROS
Very thin edge and hence very high sharpness
Generally good stability of blade
CONS
Blade only works for either left- or right-handed people, not for both
Straight cuts are difficult (which is intended for a very specific use)
Thin and hence fragile and sensitive edge
Combination grind
Almost flat grind on the upper part of the blade and convexing only in the lower 1/3 of the blade. Way of grinding of Japanese double bevel edge knives.
PROS
Generally thin blade, with added stability in edge area
Best compromise between sharpness and blade/edge stability
Less sticking/drag
CONS
More expensive, since more grinding steps