Square end mill includes long end cutting edge disposed from end portion on outer peripheral side in radial direction to center in the radial direction when a cutting edge portion is viewed from end face side, and short end cutting edges disposed from other end portions on outer peripheral side in radial direction to middles on center side in radial direction, first gashes disposed on regions from lines connecting end portions on center side in radial direction of the short end cutting edges to center in radial direction to the long end cutting edge on rear side in the rotation direction, second and third gashes disposed on rear and front sides in rotation direction of the first gashes, and all gashes formed in curved surface shapes depressed to a shank side on opposite side in axial direction of the cutting edge portion.

A cutting tool including an annular cutter body having at least one V-shaped pocket formed therein and a cutting tool cartridge configured to be received in the at least one pocket of the cutter body. The cutting tool cartridge including a main body. The main body includes a cutting head having a cutting chip control portion and a pocket configured to receive a cutting insert.

Utilities supplied through a first utility path of a turning tool holder via a docking device is supplied to a second utility path of an adjacent rotating tool holder through a communication means, there is no need to provide a complex hydraulic line, a pneumatic line and a coupler for receiving the utilities from the docking device at a rearward side of the rotating tool holder. A rearward size of the rotating tool holder may be minimized, so that even when the rotating tool holder is mounted on the turret, no interference occurs with the docking device in the rearward direction when the turret rotates. As a result, it is possible to use the rotating tool holder, to which utilities supply is necessary, even in the turret which is provide with the docking device.

The present disclosure provides a cutting tool that comprises: an end cutting edge that is formed so as to extend radially from the central axis side; a peripheral edge that forms a pair of cutting edges with the end cutting edge; and a chip discharge groove provided around the central axis. The chip discharge groove is formed by two or more grooves that include at least a major groove and a minor groove and have different helix angles from each other. The major groove that forms the peripheral edge on an edge between a peripheral side surface of the cutting tool and such major groove has a helix angle that is the smallest helix angle, and the minor groove that is in contact with the major groove and arranged with its phase shifted forward with respect to the major groove in a tool rotating direction has a helix angle that is greater than the helix angle of the major groove.