Making styrene look like concrete is much easier than it sounds! On my layout, the “JDS&E”, I decided to use sheet styrene for my service platforms in the engine facility.
I first scored the sheet into 12 foot squares using a hobby knife. I then laid the sheet flat and block sanded to remove the high spots left over from the scoring process. I cut the sheets to fit between the tracks and sanded the edges.
I then airbrushed Floquil Concrete as the base color for the platforms. After the sheets have dried, it’s time to give it the look of real sand, gravel and cement. Very lightly airbrush the entire surface with Floquil Rust.
This final step gives the concrete a brownish tint, the color of aged concrete! I, of course, then add copier toner to give it a dirty look. You may want to add stains with dirty thinner or any other weathering technique you prefer.