Just finished up the weathering job on my Lionel 4 bay I picked up at the Big E. The weathering took a good 12 hours to complete.
I started off with light washes of acrylics. Blacks first, dark rusts second and lighter rusts third. I use and electric eraser to remove and weather letters, I also use the electric to remove the red finish and create an uneven surface for the majors rust areas. I wash the rust areas with washed rust to darker harder rust and follow up with light rust washes. Then it was off to the spray booth for the light gray road dust build up. After this another run over the rust areas to highlight rust through area. The trucks were also done in the same fashion. I did do the hopper bay but no photos.