Abstract: A double-sided, indexable, polygonal turning insert includes a plurality of corners, a peripheral clearance surface, and identical upper and under sides. Along the upper side and underside, primary cutting edges, which individually include a nose edge situated in a corner and two main edges, converge toward the same and transform into auxiliary cutting edges, which separate each pair of primary cutting edges along one and the same side. Chip-directing guide surfaces are placed inside the chip surfaces of the cutting edges. The primary cutting edge has a generally positive cutting geometry such that a wedge angle of the cutting edge between the chip surface and the clearance surface is acute in arbitrary sections along the nose edge, as well as along the two main edges. In such a way, the primary cutting edge produces chips that can be guided in a careful, although distinct, way by the guide surfaces.

Abstract: A double-sided, indexable, polygonal turning insert includes a plurality of corners, a peripheral clearance surface, and identical upper and under sides. Along the upper side and underside, primary cutting edges, which individually include a nose edge situated in a corner and two main edges, converge toward the same and transform into auxiliary cutting edges, which separate each pair of primary cutting edges along one and the same side. Chip-directing guide surfaces are placed inside the chip surfaces of the cutting edges. The primary cutting edge has a generally positive cutting geometry such that a wedge angle of the cutting edge between the chip surface and the clearance surface is acute in arbitrary sections along the nose edge, as well as along the two main edges. In such a way, the primary cutting edge produces chips that can be guided in a careful, although distinct, way by the guide surfaces.