A replaceable milling head rotatable in a cutting direction about a longitudinal central axis, the central axis defining a forward direction and an opposite rearward direction, has a forward cutting portion and a rear threaded coupling portion for coupling to a shank. The cutting portion includes two or more key actuating portions which assist in mounting the milling head onto the shank. The cutting portion includes a plurality of helical chip flutes alternating with cutting edges. At least one or more of the cutting edges and flutes extend axially rearward of at least a portion of the key actuating portions.

A cutting tool assembly includes a tool body and a tool holder including a longitudinal axis around which the tool holder is configured to spin. The tool holder includes a central portion connected to the tool body comprising a fastener hole perpendicular with the longitudinal axis and configured to receive a securing fastener, wherein the fastener hole is offset from the longitudinal axis. The tool holder further includes an eccentric drive member connected to the cylindrical portion. The tool holder can optionally further include an end alignment cylinder connected to the eccentric drive member.

A rotary tool can be adapted for removing material from a workpiece such as a lower receiver. A rotary tool can have an adapter with a major diameter, and a cutter head with a minor diameter. The major diameter of the adapter can reduce deflection and chatter, while the minor diameter of the cutter head can be used to manufacture lower receivers with accuracy. The rotary tool can be adapted to be engaged with a rotary power tool.

The present invention relates to a tool (10) for machining a workpiece, comprising a cutting head (12) which comprises a sleeve (16) and a cutting element (18) which is fixed to the sleeve (16), and comprising a holder (14) to which the cutting head (12) can be detachably fixed. In an assembled state of the tool (10), the cutting head (12) and holder (14) are screwed to each other via an internal thread (40) which is arranged in the sleeve (16) and an external thread (42) which corresponds thereto and which is arranged on the holder (14). In addition, in the assembled state of the tool (10), the cutting head (12) and holder (14) contact each other along a first axial bearing surface (36) which is arranged on the sleeve (16) and a second axial bearing surface (38) which corresponds thereto and which is arranged on the holder (14), and along a first conical bearing surface (44) which is arranged on the sleeve (16) and a second conical bearing surface (46) which corresponds thereto and which is arranged on the holder (14).

A rotary milling tool has a tool holder and a milling head releasably attached thereto. The milling head has a plurality of angularly spaced apart peripherally disposed cutting edges which form an effective cutting edge. The milling head has a head through recess opening out to the head forward and rearward surfaces. The recess includes a centering region and a driven region, the driven region being axially forward of, and non-identical to, the centering region. The driven region has at least one driven surface facing opposite a rotational direction. The centering region has at least one radially inwardly facing radial centering surface located axially rearward of, and radially outward from, the at least one driven surface. The two opposing extremities of the effective cutting edge define two parallel planes respectively between which both the at least one driven surface and the at least one radial centering surface are disposed.

In this cutting tool with a replaceable cutting head, a cutting head including a cutting edge is detachably attached to a tip end portion of a shaft-like tool main body rotated around an axis in a tool rotation direction. The tool main body and the cutting head are attached to each other when an abutment surface of the tool main body on a tip surface of the tool main body abuts and adheres to an abutment surface of the cutting head on a posterior end surface of the cutting head. A recessed portion and a projecting portion able to be inserted into this recessed portion are respectively formed on the posterior end surface of the cutting head and the tip surface of the tool main body. The recessed portion and the projecting portion are formed to increase in width in a circumferential direction toward an outer peripheral side.

An object of the present invention is to provide a cutting tool that requires the smaller number of parts and can be manufactured at a lower cost. A cutting tool includes: a tool body extending along a central axis and rotatable around the central axis; a cutting insert to be mounted on an insert mounting seat of the tool body; and at least one flow passage provided inside the tool body, the at least one flow passage extending from a back end side toward a front end side of the tool body so as to supply a coolant toward at least a part of the inside of the tool body, a back end side of the at least one flow passage being open at a portion sealed by the tool body and the holding member when the holding member is coupled.

A replaceable milling head rotatable in a cutting direction about a longitudinal central axis, the central axis defining a forward direction and an opposite rearward direction, has a forward cutting portion and a rear threaded coupling portion for coupling to a shank. The cutting portion includes two or more key actuating portions which assist in mounting the milling head onto the shank. The cutting portion includes a plurality of helical chip flutes alternating with cutting edges. At least one or more of the cutting edges and flutes extend axially rearward of at least a portion of the key actuating portions.

A rotary cutting tool includes a replaceable cutting head and a tool holder. The replaceable cutting head includes a forward cutting portion and a rearward mounting portion. The mounting portion includes a male coupling member that includes a back-tapered conical external thread. The tool holder includes a female coupling member that includes an internal thread. When the rotary cutting tool is in a locked position, the external thread is threadingly engaged with the internal thread.

A rotary tool can be adapted for removing material from a workpiece such as a lower receiver. A rotary tool can have an adapter with a major diameter, and a cutter head with a minor diameter. The major diameter of the adapter can reduce deflection and chatter, while the minor diameter of the cutter head can be used to manufacture lower receivers with accuracy. The rotary tool can be adapted to be engaged with a rotary power tool.