Originally Posted by Crisis3
This will be my first brake job with the Audi. On my past cars the crack staff at that certain golden touch brake shop always told me I needed new rotors, but when I complained of the price they recommended machining as an option. Been doing that for years. I take it I've been taken?
I wouldn't say "taken," per se, but machining is generally not considered "acceptable" within the higher echelons of the car world. It is a common practice on "normal" cars, however is not an accepted practice on any German cars.
In proper practice, rotors are either good to go another round or they're not. There is a min thickness spec of the rotor. Generally speaking, if you run your finger over the edge of the rotor and can feel a sizable "lip," it's time for new rotors. On average, on a daily driven car, you should get two sets of pads to one set of rotors.
Machining will get rid of the lip, and does have the side benefit of getting you down to virgin metal, but it does this by taking away material.