Patent attributes
A rotary cutting tool is provided with a tool body having a shank portion and a neck portion, an insert attachment seat formed at the tip of the neck portion, and a cutting insert detachably mounted on the insert attachment seat so as to be coaxial with the axis line of the shank portion. The insert attachment seat is provided with a bottom surface on which a side surface which serves as a seating surface of a cutting insert is seated and a wall surface in contact with a peripheral surface of the cutting insert. On the bottom surface, a plurality of recessed grooves which are recessed from the bottom surface to extend in the circumferential direction of the neck portion, with the both ends being opened on an outer peripheral surface of the neck portion.
