If you want to easily model a typical heavily weathered covered
phosphate hopper then this paint method may work for you. First make
sure the model is clean of wax residue, soak in Bestine for best
results. Then paint the the car a dark red color (the paint job doesn’t
have to be great). I used Krylon Fusion Burgundy. Next I cut a template
of
SCL letters.
I sprayed flat white spraypaint over the template. Then I weathered the
whole car with mists of flat white spraypaint. I have yet to add
reporting marks, which are usually patches of cleaned off areas.
Overall, this simple technique renders a realistic heavily weathered
covered phosphate hopper quickly. (Model shown is a U14 prototype
slightly different from what is currently for sale at
Shapeways.)