APA Micro Layout (Part 8 Weathering the Highway overpass)

To hide the entry/exit of the layout I will install a highway overpass with concrete footings. These conceal the hole from the viewers side.

The roadway will also cast a shadow over the entrance so it will not be so obvious.

After assembly, I first brush-painted the bridge with a concrete color.

Then I applied some decals with signs and slogans that are usually found in such places. After the decals had dried I oversprayed it with Testors Dullcote. The matte finish of the Dullcote gives the surface some tooth for the weathering powders and pigments to stick to. With a bristled brush I dusted the parts with burnt umber and sienna pigments. If you inspect a concrete bridge or abutments closely, you find that all the dust and grime gets washed down with every rainfall. These different colored streaks were the effect I tried to recreate.

I sat the bridge upright and loaded a wide brush with Isopropanol Alcohol and squeezed it to the top of the pilasters and the lower concrete wall. The liquid ran down the side, washing some of the pigments down. The alcohol also dissolved some of the concrete color and bleached it out. I repeated the process until the desired effect was achieved. I also alternated between a black wash and the liquid from cleaning my brushes. You cannot overdo it if you use the blacks sparingly.

Then I turned my attention to the roadbed. I first pencilled the white separation lines with a white pencil using a straight edge. I prefer this technique over spraying them with white color. The pencil leaves a more faded appearance. Then I gave the road a black wash to highlight the expansion cuts and to tone the concrete color down. One important other feature are the rubber marks. To recreate these I used a fine brush to apply black powdered chalks to the running lines of the car tires. I used my finger tip to rub the powder all along the direction of traffic. With a brush loaded with Alcohol I dabbed the liquid randomly onto the roadbed. This created some irregular dried puddles.

The overpass will be a double lane into one direction and the opposite direction will be in the fiddle yard box. I think this is more convincing than just one lane in each direction. The cars are not correct for the era I will model.

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