An assembled chamfer mill comprises a tool holder, an extension shaft, and chamfer bits locked to two ends of the extension shaft. The chamfer bits each have upper blades and lower blades for chamfering the edges of a workpiece simultaneously. The length of a shaft body of the extension shaft may be set in various sizes. Depending on the thickness and shape of the workpiece, the shaft body having an appropriate length is selected, so as to control the distance between the two chamfer bits. Another extension shaft may be provided to connect a further chamber bit for chamfering the edges of the workpiece simultaneously.

In a dimple processing method for forming dimples on a curved surface of a workpiece, a cutting tool having a cutting edge on a rod-shaped body is rotated about a central axis of the cutting tool. The workpiece is rotated about a first axis. The cutting tool or the workpiece moves on a virtual plane through which the first axis passes or on a plane parallel to the virtual plane. The cutting tool or the workpiece moves such that the tip end of the cutting tool follows the curved surface of the workpiece. The cutting edge forms one or more dimple on the curved surface each time the cutting tool rotates.

A rotatable tool for producing a circular groove through metal cutting in a metal work piece and a method of forming the circular groove with the rotatable tool is disclosed. The rotatable tool includes a front end and a second end. The front end includes a first radially outer cutting edge and a second radially inner cutting edge, where the first radially outer cutting edge is located at a larger radial distance from the tool center axis than any other cutting edge of the rotatable tool, and where the second radially inner cutting edge is located at a smaller radial distance from the tool center axis than any other cutting edge of the rotatable tool.

A formed rotary cutting tool includes a cutting edge defining a cutting edge diameter that is increased and reduced in a direction of an axis of the tool, so as to have at least one neck portion in which the cutting edge diameter is minimized. The cutting tool includes a roughing portion which is provided on a periphery thereof and which is constituted by a succession of protrusions and recesses arranged in the direction of the axis. The roughing portion includes (i) a fine roughing portion that is provided in at least one of the at least one neck portion, and (ii) another portion that is provided in a portion that is other than the at least one of the at least one neck portion. The fine roughing portion of the roughing portion is different in characteristics from the above-described another portion of the roughing portion.

A cutting tool assembly for milling a rail top, includes a first section and a second section mounted to the first section. Each section includes a plurality of insert-receiving pockets for receiving a plurality of different types of cutting inserts. The plurality of different types of cutting inserts are arranged in a plurality of helical teeth that may be separated by a helical chip flute. In one embodiment, a first type of cutting insert is formed with a radius, R, a second type of cutting insert is formed with a radius, R1, and a third type of cutting insert is formed with a radius, R2, to perform a milling operation on three different areas of the rail top.

An assembled chamfer mill comprises a tool holder, an extension shaft, and chamfer bits locked to two ends of the extension shaft. The chamfer bits each have upper blades and lower blades for chamfering the edges of a workpiece simultaneously. The length of a shaft body of the extension shaft may be set in various sizes. Depending on the thickness and shape of the workpiece, the shaft body having an appropriate length is selected, so as to control the distance between the two chamfer bits. Another extension shaft may be provided to connect a further chamber bit for chamfering the edges of the workpiece simultaneously.

A milling tool having an operating area that is rotatable about an operating axis of rotation for milling a workpiece. The operating area has at least one milling edge extending transversely to the circumferential direction (U) of an operating axis of rotation. At least one of the at least one milling edge includes at least one milling edge portion in which a milling edge profile (P), which is defined by the radial distance (F) between the milling edge and the operating axis of rotation along the milling edge, has a non linear progression. The milling edge in the milling edge portion has a chip space, which extends radially inward toward the operating axis of rotation in relation to the milling edge. The chip space has a chip space base that follows the milling edge profile (P) at least in portions in the milling edge portion with the non-linear milling edge profile (P).

An end mill having a plurality of cutting edges on a surface of a rod-shaped main body is rotated about its longitudinal axis and is moved relative to a workpiece in a feed direction tangential and orthogonal to the longitudinal axis along the workpiece. The end mill is also moved relative to the workpiece in a reciprocal manner in the axial direction while it is moved in the feed direction. In this way, a plurality of dimples are formed by the end mill on the workpiece, such that the dimples are relatively spaced apart from each other on the workpiece. The plurality of dimples are arranged side by side in the feed direction along a line inclined at a predetermined angle relative to the feed direction so as to be offset while partially overlapping with respect to each other in the axial direction.

A milling tool, preferably a fir tree cutter, having an operating area which is rotatable about an operating axis of rotation for milling a workpiece and comprises a milling edge which extends transversely to the circumferential direction (U) of an operating axis of rotation, wherein the at least one milling edge includes at least one milling edge portion in which a milling edge profile (P), which is defined by the radial distance (F) between the milling edge and the operating axis of rotation along the milling edge, comprises a non-linear progression, wherein the milling edge in the milling edge portion comprises a chip space, which extends radially inward toward the operating axis of rotation in relation to the milling edge and comprises a chip space base which follows the milling edge profile (P) at least in portions in the milling edge portion with the non-linear milling edge profile (P).

An end mill includes a major-diameter shank, a cone-shaped connector portion disposed at the end of the shank, a minor-diameter body disposed by way of the connector portion coaxially therewith, a toothed element disposed at the leading end of the body, an installation recess dented slightly in the toothed element, and a cutting edge held in the installation recess so as to swell in the shape of an arc to protrude from an outer peripheral face of the body.