The step being performed in a state where a wheel body is fixed to be prevented from rotating around a rotation axis while a cutting edge of a cutting tool is in contact with the three-dimensional shape surface of the design surface in the wheel body, the cutting tool being three-dimensionally and continuously moved relatively along the three-dimensional shape surface while being changed in direction with respect to the three-dimensional shape surface to allow a rake face of the cutting tool to face a tool travel direction to perform three-dimensional continuous cutting processing that allows a specular glossy surface to be automatically formed in the three-dimensional shape surface, the specular glossy surface being finished into a processed surface having a high metallic gloss property by exposing the base metal.

An outer member and an inner member constituting a wheel bearing device are assembled and the brake rotor is fixed to the hub ring of the inner member. In this state, the pad slide surfaces of the brake rotor are lathed with the reference provided by a wheel pilot end surface. Alternatively, the wheel pilot end surface of the hub ring by chucking the knuckle pilot of the outer member with the wheel bearing device put in its assembled state, and the pad slide surfaces of the brake rotor are lathed with the reference provided by the wheel pilot end surface.

The step being performed in a state where a wheel body is fixed to be prevented from rotating around a rotation axis while a cutting edge of a cutting tool is in contact with the three-dimensional shape surface of the design surface in the wheel body, the cutting tool being three-dimensionally and continuously moved relatively along the three-dimensional shape surface while being changed in direction with respect to the three-dimensional shape surface to allow a rake face of the cutting tool to face a tool travel direction to perform three-dimensional continuous cutting processing that allows a specular glossy surface to be automatically formed in the three-dimensional shape surface, the specular glossy surface being finished into a processed surface having a high metallic gloss property by exposing the base metal.

An axial section of a continuous portion where an outer peripheral surface of a spindle portion of a main spindle in which a punch is installed is continuous with an outer peripheral surface of a punch holder is formed of a first circular arc joined to the outer peripheral surface of the spindle portion and a second circular arc joined to the outer peripheral surface of the punch holder. The first circular arc and the second circular arc are in contact with each other. The second circular arc is smaller than the first circular arc in curvature radius.