Weathering stuff

Weathering using salt

About ten or so years ago I was online looking at military modeling websites and came across an article that described a weathering technique called salt weathering. Since then I’ve tried it on a few models and the results are remarkable.

The lead image illustrates the salt weathering technique to simulate paint peeling off the galvanised metal roof of the lean-to.

Here’s a close-up of the roof and lean-to at the start

So…what is salt weathering? It is a method used to simulate paint chipping using table salt. I’ll demonstrate the steps below using the roof.

Step 1 – First, paint the roof with an underlying rust or galvanized color that you want to show through. I call this the base layer. The base layer was a dusting of red oxide to simulate rust. I used that same mix on the roof shown in the photo above.

Step 2 – Allow the base coat to dry completely. Meanwhile, gather table salt, household rubbing alcohol, a sprayer, and a container for your project because salt weathering is messy. For my project I used two kinds of salt—fine table salt and coarse sea salt. The container once held ice cream. 

Step 3 – Spray the roof casting with the rubbing alcohol. Many modelers use water for this step, but I strongly recommend using rubbing alcohol. It is amazingly effective in breaking surface tension, which allows better coverage for the salt.

 

 

 
Step 4 – While the alcohol is wet, sprinkle on the salt. Don’t completely cover the roof with salt—just sprinkle it on. The photo above shows how the roof looked after the salt was applied.

Step 5 – Now let the whole mess dry for a day.

Step 6 – Once the roof and salt are dry, carefully airbrush the roof—with the salt still applied—with the correct roof colour, such as grey. Carefully handle the roof while painting as the salt can flake off with the slightest breath or touch.

Step 7 – Here’s the fun part. After the paint is completely dry, carefully rub off the salt. The color underneath—the base colour applied in Step 1—will appear when the salt is removed. The photo above shows how the roof looked after the salt was removed.

Step 8 – Next, go back over the running boards and roof seam caps with the original car color. Running boards and seam caps were made of different material that the rest of the roof, so they weathered differently. Touching up the running boards and seam caps with the car color provides a contrast with the weathered roof.

Step 9 – The splotchy uneven finish gives the appearance of peeling paint. Using the homemade galvanized color mix, I went back over a few places to blend the colors a little more. I used the little yellow brush seen a couple photos back for the job. I also added a little AIM Weathering Powders Soot Black, applied with a small brush, to darken the roof in a few places to represent soot and cinders. To finish the job, I sealed the roof with a shot of Testors Dullcote.

Salt Weathering is easy but I recommend you practice on a few models first. The first time I tried salt weathering I finished three roofs: One turned out good, and the other two were “fails”. However, I learned how much salt to add and where to add it, and that was really helpful for later attempts.

The next level of salt weathering is looking at actual prototype weathering and applying the salt in specific places to simulate specific weathering patterns. Let prototype photos be your guide.

What else can you use salt weathering on? Oil tanks, bridges, and anything made of steel or metal on or along the railroad. I think it could be used with excellent results on storage tanks used by small town oil dealers.

I hope you find the salt weathering technique useful!