Patent ID: 7677144

Claim:
A method of machining and balancing a brake drum comprising the steps of: providing a brake drum having a generally cylindrical body having a central radial axis and an open end and a hub end, the hub end comprising an inner facing surface and an outer facing surface, the brake drum body including an outer radial surface and an inner radial surface, the outer radial surface including a radial edge, holding the radial edge of the open end in a chuck assembly, machining the inner facing surface and outer facing surface of the hub end, and machining the outer radial surface and inner radial surface of the brake drum body in an operation to radially balance the brake drum about the central radial axis, wherein the chuck assembly holds the brake drum at selected locations along the radial edge of the open end to allow substantially all of the outer radial surface of the brake drum to be machined, and exposing the brake drum while held in the chuck assembly to an outside radial cutting head for machining the outer radial surface of the brake drum and an inside radial cutting head for machining the inner radial surface of the brake drum, and exposing the brake drum while held in the chuck assembly to an inside vertical cutting head for machining the inner facing surface of the hub end and an outside vertical cutting head for machining the outer facing surface of the hub end.