Abstract: An apparatus (10) particularly suited for use for purposes of effectuating the cutting to length of continuous lengths of relatively thick, soft stock sheet material (14) such as sheets of styrofoam which have a thickness of six inches or greater. The subject apparatus (10) includes a carriage assembly (32) mounted for movement on a support base (16). The carriage assembly (32) is driven by motor means (34) operatively connected thereto. The motor means (34) is operative to cause the carriage assembly (32) to move in a triangular path while undergoing movement in two planes at a speed which varies directly with the speed at which the soft stock sheet material (14) that is to be cut to length in the subject apparatus (10) is fed therethrough. A knife means (68) is supported on the carriage assembly (32) for movement therewith such that as the carriage assembly (32) moves in a triangular path the knife means (68) likewise moves in a triangular path, i.e., down and forward.