I have noticed that the dirt trails on my CMX track cleaning car are offset to one side. This enables double use out of one piece of cloth. You meerly reverse the car and a new section of cloth is rubbing the track. Is mine unique or are they designed that way?
They must be designed that way because mine is the same. That doubles the amount of use you can get out of one pad.
That would make sense. Could it be from running on curved track?
No, because on our 20 x 40 foot HO scale layout there is far more straight track than curved. It would be true for curved track only if you were just running in a circle, maybe, but not if you have a lot of straight sections.
Mine is the same way as well.