BrakeSaver Nation relies on the Pro-Cut on-car brake lathe to effectively match your rotors to the hub so they turn without wobble, or runout. You may know that every wheel is individually balanced before it's mounted on your car. The same principal holds true for your brakes - for the best long-term performance each rotor should be specifically tailored, or "matched", to the hub so there is less than 0.002" (about the thickness of a hair) of runout per rotation.
HOW ROTOR MATCHING WORKS A vehicle is brought into the shop, raised on a lift and the Pro-Cut lathe is actually attached to the hub of the vehicle. Computer-driven technology aligns the lathe so that a thin section of the rotor (about twice the thickness of a hair) can be removed in a manner that leaves it perfectly aligned at 90° to the hub. This process is supported by virtually every auto manufacturer and in fact mandated by many (See Credentials).
It should be noted that rotors are designed to allow this machining process at least once before falling below minimum thickness at which point it should be recycled.
WHY ROTOR MATCHING IS BETTER
A rotor that is matched to the hub wears evenly and is unlikely to develop pulsation. In all likelihood it will last until the pads wear out; usually 30,000 or more. So in addition saving the rotor in the first place, you get a second full lifetime of high performance braking.
In summary, rotor matching is:
SAFER
Brakes that are returned to manufacturer's specifications work as designed and are the safest systems on the road.
LESS EXPENSIVE
Restoring old rotors is less expensive than buying and installing new.
BETTER PERFORMANCE
By matching the old rotors so they wear evenly, your brakes perform better, last longer and stop better.
KINDER TO THE ENVIRONMENT
Saving your old rotors keeps them out of the waste stream for another service cycle, sometimes as long as 5 years!