Constant Grinding of my Brakes on my Rotors.?

If the measurement of thickness at the bottom of the grooves is below factory specifications for minimum thickness, the rotors must be replaced. If rotors remain thinner than spec, they will overheat and warp, thus causing a dangerous condition. Do yourself a favor and replace the rotors when pads are done. Turning rotors has always been a waste of time and very rarely achieves desired brake operation. You can always buy the parts at Auto Zone and pay a friend to do it on the side.