Rotors and brake pads

[aguy0523]

I have heard that some people scuff there rotors with 400grit sandpaper or others with steel wool. What is that for and how often do you do it?

[Super Dave]

I usually scotch brite mine occasionally.  After a rain race or some good maintanance.  

If I'm changing from a different kind of pad, even in the same brand, I will clean them with scotch brite.