I noticed this during the winter, but didn’t connect the dots until yesterday. The stainless steel rails through my concrete Walk Crossing have rusted over the winter. These rails have been embedded in concrete for over 5 years with no ill effects until recently. What changed? Since late last summer 12V @ 5A power charges the rails for a lighting buss 12 or more hours a day. Only one polarity rail is rusting…
Had I realized this would happen I could have shut the power off to this section as it is still controlled by block switches. I actually attempted to get this look once with the steel wool and vinegar solution, but it bleached away quickly in the sun. I guess I just have to swap polarity for the next six months to even it out
The track condition is not an issue as I am 100% battery or live steam power for locos but I might try and polish the rail tops for appearance sake.