Adding Dull Coat and Washing with IPA for a Hazed Washed-out Look 

For most of my rolling stock, I apply a very light burnt umber wash to make the cars not look off the showroom floor brand new. For the roofs, I spray on a dull coat and let dray. Once the dull coat is dry, I brush on IPA (isopropyl alcohol). As the IPA dries, the surface takes on this hazed sun weathered look. It's very easy to accomplish and the results are varied which gives it a realistic prototypical look.
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Music:
Slow Movin; Cameo
• Slow Movin