To provide a stable joint bolt of good quality by continuously removing burrs remaining in crossing holes inside many joint bolts.

The finishing device comprises a first station for setting each joint bolt on a fixture rotatably supported on a rotary table and removing it from the fixture, a second station for injecting high pressure media containing abrasive grains from a first nozzle to a vertical hole in the axial direction of the vertical hole while rotating the joint bolt set on the fixture in the axial center of the vertical hole, a third station for injecting high pressure media from a second nozzle to a horizontal hole in the radial direction of the vertical hole while rotating the joint bolt set on the fixture in the axial center of the vertical hole, and a fourth station for cleaning the joint bolt with cleaning fluid and then performing air blow. While rotating the rotary table with a predetermined tact time, predetermined work is sequentially applied to the joint bolts in each station.