There is more to turning rotors than throwing them on a machine and then
returning them to the car. I turn the rotors, then use a surfacing disk on
a die grinder to smooth out the grooves from the machine, then wash the
rotors in soap and water to remove any metal dust left by the turning
operation. This works every time. Cost to turn and resurface the rotors is
$20 per pair (off the car). I can't answer your question, but maybe you can
answer it yourself now.
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