Regardless of scale, I run a home-made track cleaner car on most of my trains to wipe rails whenever I run trains. This not only keeps rails clean for consistently reliable no-stall operation, it absolutely minimizes the need to eventually clean wheels. I've been doing this for 20+ years in HO, N, HOn30 and O gauges.
There is an old HO trick of using a masonite block to slide on the rails under a boxcar, with two alinement pins going up into the car. I simply modified that idea by using a metal plate with a denim cloth pad which is easily replaced when it gets dirty. The cloth pads collect the crud instead of allowing it to be redistributed on wheels and rails.
I can live with the appearance of a track cleaner car on most trains for the sake of operational reliability and clean wheels. With some creativity you can make your own track cleaner cars with a discrete appearance to run in regular trains, for any scale or gauge or type of equipment.
