The Pacific Coast Air Line was originally an On30 narrow gauge railroad. I built a second bridge for the "ill-fated" OO/HO in the 1870's project. I had two highway bridges built in O scale. The O scale bridges were made of wood painted with Kilz primer and stained with India/Ink and alcohol. For the new, smaller scale I was going to use styrene. My usual method of making styrene look like weathered wood is to prime it white and stain the primer with a wash.
Above, the original O scale bridge of wood
At right a plastic water tank painted with Kilz primer and stained with Rit Liquid dye.
While preparing a web article about building my highway bridge I discovered a different stain and method. I was trying to make the gouges and textures pop out for my photo of roughing the styrene. I use a fabric paint called Dye-na-flow to color faux fur. I applied some to the roughed styrene just hoping it would accentuate the roughness. The stain made the naked rough styrene look like wood.
The Dye-na-flow has given me the most realistic weathered wood coloration on styrene yet.
This is black Dye-na-flow fabric paint it is available on the net. It will color acrylic fabrics.
Texture the plastic with an initial sanding of 220 grit sandpaper. Make sure there are no shiny spots, the Dyn-a-flow will only stain the rough texture. I follow with 50 grit sandpaper and really rough the surface. Take a knife and randomly rough up boards to show deterioration from the weather.
Apply the Dye-na-flow directly from the bottle. If it is too dark add a little water to the paint on the plastic. Allow the paint to mottle and puddle.
Make sure all the sanding is with the "grain". If there are any "mistakes" readjust them with a knife by making more texture.
Since not all plastic is white, experimenting with different white primers followed. This is a deck from and IHC old time rail and tie car.
I painted the left side with gesso and the right side with acrylic craft paint.
I stained the deck with the Dye-na-flow. The results were really good.
When I mix styrene with wood it should really have the same coloration. I took a piece of basswood scribed siding and primered the piece with Gesso.
After staining the primer with Dye-na-flow the results were really good. The grain in the wood produced a line across the piece but that was acceptable.
The Dye-na-flow has proved to be a useful tool. The black is a true black. It colors with neither a blue hue or a brown.
The Dye-na-flow will give the raw styrene a realistic old wood look.
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