60, a continuous cutting action is prevented, because soon the blade cannot force apart the sides of the cut made by the advancing edge, and the knife is brought to rest.

In this case, it is practically only the first action which has taken place.
Both the actions, the cutting and the splitting, must take place together to produce a true continuous cut.

The edge must always be in contact with the solid material, and the blade must always be pushing aside the portions which have been cut.

This can happen only when the material on one side of the blade is thin enough and weak enough to be readily bent out of the way without opening a split in front of the cutting edge.

This cutting action may take place either along the grain, Fig.