Cutting portion regions of replaceable blades that extrude outward in a radial direction at a plurality of portions in a peripheral direction of an outer periphery of a body of a finger joint cutter are arranged in that, as for a cutting portion material that comprises cutting edge, tip end cutting portions are formed of a steel material of high hardness and base portion side cutting portions, which are the remaining portions, are formed of a steel material that exhibits a higher toughness than that of the tip end cutting portions. It is possible to improve the wear resistance through the tip end cutting portions and to improve the chipping resistance by the base portion side cutting portions. The steel material of high hardness comprising the tip end cutting portions and the steel material of high toughness comprising the base portion side cutting portions are successively joined through forge welding.