Hollow grinding produces a concave form on the knife blade. Products made by this type of grinding are pocket knives, smaller kitchen knives and multi-tools. This process uses Type 6 cup wheels being used simultaneously. Hollow grind gives the knife blade a thinner blade producing a knife that will cut quickly, with minimal effort.
Concave grinding of knives
Machine types: e.g. Berger, Siepmann
Surface speed: vs=max 32 m/s