After struggling for years to come up with a simple and effective track cleaner I have finally managed to come up with something that actually works well and costs almost nothing. I started with a gondola car and attached a piece of aluminum fascia to the underside (see the white piece in the 3rd photo). Then attach a piece of magic eraser with a screw and a plastic washer (also shows in the photos). A fair amount of weight is needed in the gondola ( I used 2 rolls of solder). Then wet the eraser with rubbing alcohol and pull it with any locomotive. It is best not to have any extra cars as the cleaner car is quite heavy and tends to derail other cars. After a few passes around the track clean the eraser material with a rag that is also wetted with alcohol. The oil and dirt wipe off very easily if you do this promptly after cleaning the track. Simple and works great.