I clean mine while the loco is on the track . I do this by wetting a paper towel with Windex or some other track cleaning fluid and then place it across the tracks. I then run the loco back and forth over the towel and shift it ( the towel ) on each pass. You just have to adjust the towel as required to do this, but for heavy locos it beats taking the loco off the rails. The rollers also get cleaned.
Does any body else have any wheel cleaning hints?
Bob C.