02-28-2015, 12:04 PM
Turn off the lights and run a locomotive. If you have visible sparks, each spark creates a bit of black carbon that can be picked up by the wheels of the following cars. I think the carbon may be a bit sticky and result in dirt build up. You also might try using a portable room air purifier with a hepa filter in the office where your railroad is located. Also on the Model Railroad Hobbyist forum, there has been an extensive discussion on using a coat of graphite on the rails. The guys who have tried graphite, thoroughly clean the rails and the wheels on both the locomotives and the rolling stock. They then rub a graphite stick on all of the rails of their layout. The graphite stops the arcing between the locomotive wheels and the rails.