Provided is a rotary milling tool capable of finishing a milled surface to produce a smooth and glossy surface. A rotary milling tool in which a plurality of chip discharge grooves (2) are provided to the outer periphery of a tip part of a tool body (1), the plurality of chip discharge grooves (2) extending from the tool tip toward the tool base, and bottom blades (5, 6) are provided to an intersection ridge part at the intersection of a rake surface (3) of the chip discharge grooves (2) and a tip flank surface (4) of the tool body (1), each of the bottom blades (5, 6) being formed integrally with the tool body (1), wherein a convex edge (7) that is convex toward a tool-axis-direction tip is formed on at least one of the bottom blades (5, 6), and the convex edge (7) is formed by the connection of a plurality of linear edges that are substantially linear.

A corner radius end mill includes a tooth adjacent a helically extending flute. The tooth includes axial and radial relief surfaces connected by a corner relief surface, as well as rake surface having a rake ridge. The rake ridge is continuously curved from a bisector line until at least an axial location rearward of the corner relief surface.

In one aspect, elongated rotary cutting tools such as end mills are described herein which may provide one or more advantages over prior designs. For example, in some embodiments, cutting tools described herein can provide reduced wear rates at corner cutting edges, may permit high ramp angles during processing up to and including 45 ramp angles, and/or increased tool life.

A cutting member comprising a cutting edge (S.sub.1,S.sub.2,S.sub.i) defining a cutting envelope and configured for removing material from a workpiece leaving therein a corner of angle . The cutting edge comprises a first cutting segment (S.sub.1) and a second cutting segment (S.sub.2) spaced from the first cutting segment (S.sub.2). Respective first and second imaginary tangents (T.sub.1,T.sub.2) of the first and second cutting segments (S.sub.1,S.sub.2) intersect one another at point O located outside the cutting envelope, forming an angle corresponding to angle , thereby defining a cutting frame at least a portion of which extends beyond the cutting envelope. The cutting edge further comprises an adjoining cutting segment (S.sub.i), extending between and bridging the first cutting segment (S.sub.1) and the second cutting segment (S.sub.2), and at least partially contained within the cutting frame. The cutting member further comprises at least one auxiliary cutting element (AT.sub.1,AT.sub.2) comprising an auxiliary cutting edge (CE,CE) extending generally along one of the imaginary tangents (T.sub.1,T.sub.2) and beyond the cutting envelope. The auxiliary cutting edge (CE,CE) does not intersect the other of the imaginary tangents (CE,CE) and/or a bisector (B) of the angle .

A corner radius end mill includes a tooth adjacent a helically extending flute. The tooth includes axial and radial relief surfaces connected by a corner relief surface, as well as rake surface having a rake ridge. The rake ridge is continuously curved from a bisector line until at least an axial location rearward of the corner relief surface.

A cutting element for use in a cutting operation, comprising a cutting edge (CE) capable of cutting out material from a workpiece during the operation, to form therein a workpiece corner of angle alpha. There exists at least one view of the cutting edge in which a portion of the cutting edge is delimitable by a first (L1) and a second (L2) line oriented tangentially to the portion of the cutting edge portion at respective tangency points A and B. The lines form therebetween a cutting angle corresponding to the workpiece corner angle alpha and have a vertex 0. For a bisector of the cutting angle intersecting the portion of the cutting edge at the point C, the projection C of the point C of the portion of the cutting edge on a line OL passing through the vertex 0 perpendicularly to the plane of the one view is located between projections A1 and B of the respective points A and B of the portion of the cutting edge on the line OL.

A multi-flute endmill including a cutting edge part having multiple cutting edges and flutes formed between adjacent cutting edges in a rotation direction around the tool axis O. A rake face of each cutting edge is formed from a rake face of an end cutting edge from the tool axis O side to the outer peripheral side of a shank, an adjacent rake face of a corner R edge that forms a surface different from the rake face of the end cutting edge, and an adjacent rake face of a peripheral cutting edge that forms a surface different from the rake face of the corner R edge. A gash is formed between the rake face of the end cutting edge and a flank of an end cutting edge that is adjacent on a forward side thereof in the rotation direction R.

Multi-flute endmill having a cutting edge rake face formed from a side of a rotation axis to a peripheral side in a radial direction, and having an end cutting edge rake face. A peripheral cutting edge rake face adjacent to the end cutting edge rake face forms a face different from the end cutting edge rake face and serves as the rake face of a corner edge. An intersection between a convex ridge line is located in a boundary between the rake faces of the end cutting edge and peripheral cutting edge. A convex ridge line is located in a boundary between the end cutting edge rake face and a bottom surface of the flute is moved into the side of the rotation axis in the radial direction with respect to a boundary between the flank face of a corner edge and the flank face of the end cutting edge.