Abstract: A cutterhead having a drum surface with a series of knife retainers distributed about the surface. The longitudinal extension of the knife retainers defines an angle ? with the axis of rotation of the cutterhead, and a knife is mounted to the knife retainer. The knife is configured such that a cutting edge of the knife extends parallel to the axis of rotation.

Abstract: A cutterhead having a drum surface with a series of knife retainers distributed about the surface. The longitudinal extension of the knife retainers defines an angle a with the axis of rotation of the cutterhead, and a knife is mounted to the knife retainer. The knife is configured such that a cutting edge of the knife extends parallel to the axis of rotation.

Abstract: A forage harvester cutterhead includes knife holders which each, in one embodiment, form a major portion of a smooth, curved impeller blade surface, which in a second embodiment form a portion of an impeller blade surface with the major portion of the impeller blade surface being defined by a replaceable sheet metal insert that is held in place by a rail located in a recess of the knife holder, and which in a third embodiment form a portion of an impeller blade surface with a major portion of the impeller blade surface being defined by a surface of an appendage of a replaceable rail located in a recess of the knife holder.