I purchased a used layout a few years ago which was approximately 10-15 years old, and recently acquired a lit magnifyer which I now use to inspect the tracks. In doing so, I discovered light abrasive marks on the rerailers and plastic switch components near the track which run parallel to the rails. The naked eye could not pick these up. Now I am wondering if the previous owner sanded the rails, which at the time, he denied ever sanding the tracks. Could it be caused by a bright boy eraser or anything else that may have made these marks over time? (Assuming he was telling the truth.) I read pros and cons for sanding the rails in this and other forums and uncertain if there wil be any short or long term implications. I have had the set for 2 years and have extensively relandscaped it and continuing to do so, and have no problem with any of my locos running any of the sections. I clean it regularly with alcohol and keep a dust cover on it. I haven't noticed any corrosion.
I can't vouch for whether they were telling you the truth or not, but I in past have sanded down the plastic guardrails on commercial turnouts as they can sometimes catch on passing Micro-Trains couplers.
