the stacked tolerances of the hub and rotor and the pad contacting surface of the rotor is cut so that it maintains a planar configuration while it is in motion on the hub before the technician removes a brake rotor from a vehicle lie or she first uses a dial indicator to take a run out reading on the rotor and if the measurements indicate an excessive amount of run out the technician will indicate the high spots on the rotor with a marker before the rotor is removed for repair the technician locates a common stud on the hub and marks it accordingly to enable the technician to realign the rotor the way it was mounted before it was removed from the vehicle once the vehicle is marked to enable proper realignment the technician will remove the rotor and assemble it on the brake lathe using the zero run out adapter first the adapter mounting arbor 24 is mounted on the brake lathe shaft 46 then the first adapter fixed offset plate 26 is placed on the arbor so that key 54 is placed in key way 44 the set screw 33 is tightened locking the fixed offset plate 26 on the mounting arbor 24 the first adapter movable offset plate 28 is placed or the arbor as described above the first and second plates are initially mounted so that the zero position indicator groove 58 on the fixed plate member and the 0 000 inch line on the notched indicia 29 of the movable plate member are linearly aligned next the technician rotates the movable plate 28 so that the run out measurement recorded from the examination of the rotor on the vehicle before it was removed from the vehicle is aligned with the zero position.