How do artists simulate weathered metal effects on polypropylene surfaces?

Artists simulate weathered metal effects on polypropylene surfaces using a combination of painting techniques and texturing methods. First, they apply a base coat of metallic paint, often using shades like gunmetal or bronze. Next, layers of acrylic washes in browns, oranges, and blacks are brushed or sponged to create rust and oxidation effects. Dry brushing with lighter metallic tones highlights raised areas, while chipping mediums or salt techniques produce authentic flaking patterns. Finally, sealants protect the finish while maintaining its realistic appearance. This process transforms lightweight polypropylene into convincing faux metal for props, cosplay armor, and scale models.