Apparatus and method of machining brake components

A method of machining a part having an annular surface comprising:

• providing a part having an annular surface coaxially disposed about an axis of rotation;
• providing an electrode assembly including a plurality of electrodes and each electrode having an associated discharge surface, wherein the electrodes are disposed such that the discharge surfaces are aligned in a plane;
• rotating the part in a first direction about the axis of rotation;
• and
• machining the annular surface of the part by moving the electrode discharge surfaces within the plane simultaneously moving one of the electrodes near the annular surface of the part to create a spark therebetween while moving another one of the electrodes away from annular surface of the part to prevent a spark therebetween.

A method of machining a brake rotor comprising:

• providing a brake rotor having an axis of rotation and an annular friction section having a friction surface coaxially disposed about the axis of rotation;
• providing an electrode assembly including a plurality of electrodes disposed in a circumferentially spaced apart relationship forming an electrode ring, the electrodes having discharge surfaces aligned in a plane and circumferentially spaced apart around the ring such that each electrode discharge surface forms a separate sector of the electrode ring;
• rotating the electrode assembly so that the electrode discharge surfaces move within the plane;
• rotating the rotor about the axis of rotation;
• and
• moving the electrode discharge surfaces and the rotor friction section sufficiently close to each other to form sparks therebetween to vaporize portions of the friction section.

A method of machining a brake rotor comprising:

• providing a brake rotor having an axis of rotation, a friction section having an annular friction surface coaxially disposed about the axis of rotation, a hat wall and a groove disposed between the hat wall and the fiction surface;
• providing an electrode assembly including a plurality of electrodes disposed in a circumferentially spaced apart relationship forming an electrode ring having a radially outer edge, the electrodes having discharge surfaces aligned in a plane and circumferentially spaced apart around the electrode ring;
• and
• machining the brake rotor by simultaneously rotating the rotor about the rotor axis of rotation, and rotating the electrode assembly so that the electrode discharge surfaces move within the plane and the radially outer edge of the electrode ring passes over the rotor groove to prevent sparks at the radially outer edge of the electrode ring.