Weathering Freight Cars with an Airbrush
by Vincent Peri
To weather freight cars with coats of rust and grime, first mix 4 parts Floquil Rust with 1 part Floquil engine black or grimy black. Thin this mixture with Floquil Airbrush thinner so that you have 1 part paint mixture to 5 or more parts thinner. Test spray this on a scrap piece of styrene so that you get a feel for how it goes on. Different weathering patterns can be achieved by moving the brush closer to or farther from the styrene. When you are satisfied with your ability to control the final results, you can begin spraying your freight car.
For heavy weathering of this Rock Island boxcar, I started spraying the car lightly with an up and down motion while moving the brush from car end to car end. Next, I sprayed the car ends using the same technique. I used light coats at first, then I applied extra coats over spots where I wanted more grime/rust. I repeated until I had the general weathering effect I wanted. I use the same procedure with the freight trucks.
Of course, I had to be alert for areas of the car that were not getting enough weathering spray. Crevices around the doors and along both sides of the boxcar’s support ribs usually need more attention, as well as roof overhang areas. I used a fine spray in those trouble spots and gradually build up the weathering until it looked right. Photos of actual freight cars will be very helpful in determining proper weathering patterns around such surface details. Oh, and don’t forget the roof. Some roofs rust, while others tarnish to a streaky dark/light gray pattern.
Once I have heavily weathered a car, the car number, reporting marks, and data are often unreadable. When real cars get that weathered, usually someone will clean the grime so that the info can be read. To achieve that effect, I use very little paint thinner on a Q-tip to carefully dab away the offending paint after it has dried for about 30 minutes. Once I reach the original manufacturer’s coat of paint, I slowly twirl the same dirty Q-tip over the area to leave realistic streaks of rust/grime to duplicate new weathering that has occurred since the reporting marks and data were cleaned.
To weather the Soo Line Grain Hopper, gradually build up light coats of the mixture of Floquil rust, Floquil engine black and Airbrush Thinner (see the CNW box car) so that there is a heavy but uneven coat of rust/grime on the car. Stop when you are satisfied with the results. Let the weathering dry for a few hours.
Next, lay the car on its side for the next step. Take some thinner in a pipette and apply a very light dribble across the upper portion of the car. This dissolves the recently applied weathering instantly, so be ready to quickly but LIGHTLY wipe the thinner off in a downward motion with a paper towel so that most (but not all) of the weathering is removed in some areas.
On this cleaned area you may want to apply a very light wash of rust/black to dull any shiny spots. Once the wash dries, then, you can use a small paint brush with diluted artist’s acrylic paints (raw sienna, burnt sienna, black) to streak on more rust and grime as desired. I find that doing this procedure on only one side of a car results in a more prototypical appearance, but if you like, repeat the process on the car’s other side after letting the first side dry for a day or longer. Finally, allow the finished car to dry for a day or two, then Dull Coat it.
The Illinois Grain Corp. car can be weathered using the paint mix already listed. This car is lightly weathered along the bottom of the car. To achieve this effect, simply hold the car at a 45 degree angle, then with an airbrush held slightly below the car, quickly move the airbrush across the car so that a light layer of weathering mix is deposited mostly on the lower sides. Once you have the effect you want, give the roof a light coat of weathering too. A very light coat can also be applied to the entire car sides using the up and down motion of the airbrush while moving it along the length of the car.
Photos by Jeff Junker