Abstract: A spherical cutter includes a spherically shaped body having open and closed ends defining a central cavity, multipoint cutting edges disposed along a circular rim at the open end, and the spherically shaped body generally defined by a radius and an origin. The cutting edges may be provided on cutting inserts removably attached to support teeth circumferentially disposed along the rim. The spherical cutter may be mounted to a rotatable spindle of a multi-axis computer numerically controlled machine with the radius and the origin located along a rotational axis of the spindle. The machine may be used for machining a cylindrical blank to form a plurality of circumferentially spaced apart integral rotor blades extending radially outwardly from a hub by machining each of the slots along a spherical surface defined by the radius and the origin.

Abstract: A method for conditioning a superabrasive grinding tool having a cutting surface includes truing the grinding tool by moving the cutting surface against a truing device to shape the cutting surface into a preselected profile, and subsequently moving the cutting surface against a sacrificial member so that the binder of the grinding tool is worn down, creating a plurality of spaces between the superabrasive particles. The spaces provide a flowpath for coolant and cutting chips during a subsequent machining process on a workpiece. Localized overheating or “burning” of the workpiece is thus avoided.