Question about track corrosion

Hello all,

I have been a lurker for a couple weeks now, after looking all over the internet, and this forum seems to be the best I could find in terms of courtesy and knowledge. I bought a SCX digital system with pitbox, brand new, and some used tracks on ebay. My problem is that there is some kind of black corrosion on the power strips, a little on the new pieces, and a lot more on the older used tracks from ebay. Because of that, the braids on all my cars get dirty real quick, and hard to clean. The cars run erratically because of that bad contact with the track.

I did a lot of reading but did not really find an anwer to my questions so here they are:

How to best remove that corrosion without damaging the original surface of the power strips? I tried 3M pads, and 600 grit sandpaper, but I am afraid to do more damage than good.

What is the best way to protect the tracks from corrosion?

Out of the factory, is there a plating (such as nickel for example) on the power strips?

Did anybody try a brush on type electroplating on power strips to prevent corrosion?

What's the best way to clean the braids?

Any help is appreciated,

Regards
Georges