To stably, accurately, and finely adjust oscillation of a cutting edge even when width of a tool body is not secured to be large enough.

A cartridge 40 having a tip 30 having a cutting edge 33 is inserted into a recessed part 20 formed on the outer peripheral side of one side surface 12 of substantially circular shape of the tool body 11, thereby being mounted via a clamp wedge 44. A recessed place 50 for passing an adjusting wedge 60 is formed in a rear end surface 42 positioned on the opposite side in the axis O direction against the cutting edge 33 in the cartridge 40. Inserting the adjusting wedge 60 into the recessed place 50 presses the cartridge 40 on the X direction side, thereby adjusting the oscillation of the cutting edge 33 in the X direction side. The recessed place 50 for passing an adjusting wedge 60 is formed in a substantially central part of the rear end surface 42 of the cartridge 40 in the rotating direction T.