I only had about 2 days to weather this car for a charity auction. Because of time constraints, I had to work fast, and use some techniques and products that I normally don't use. Every little step is not documented, but it shows the overall progression. Explanation of steps are included in the individual photos.
Atlas HO model, out of the box.
The initial fade was done with an airbrush. Unfortunately, I think my paint was too thick, and I got a lot of overspray effect. Portions were masked off, to later represent patches
To fade the car even more, I did a filter with Zinc White Oil paint and mineral spirits. I applied the white paint with a smaller brush on a few areas over the car, and then used a larger flat brush, just slightly dampened with mineral spirits to blend paint over the entire surface.
While the oils were drying, I used a medium flat brush to paint the roof with Vallejo Acrylics. Dark Rust and German Camo Black Brown. Leave the seams between the roof panels silver to simulate roof sealant. I also added some darker rust pigments.
For the rust streaks, I tried something a bit new and faster than my usual small brushes. I used and smaller filbert brush, with a little bit of burnt umber and basically dry brused on the vertical streaks.
On some of the longer, narrow streaks, I used the side of a scrap piece of plastic to use as a guide for my brush. Use another brush, just damp with spirits to erase or straighten any crooked streaks.
For the large rust pits, I used a Copic Marker, I believe it was "Dark Walnut". It made for fast work, but I wasn't too happy with the look. Hindsight, I probably would have just used an acrylic paint like the Vallejo Dark Rust.
All the rust work is basically done, and with the masking tape removed, you can see the "patch" that was made.
The final step was to add some graffiti, the FRA stripes, and COTS label.