We "rattle can" spray painted, then brush painted the parts picturedusing simple hand techniques and thinned acrylic craft store paints (Americana brand, Craftsmart brand, DecoArt brand) in the following colours...
Silver - new galvanized metal
Light Grey - oxidized galvanized metal
Burnt Umber / Orange - fresh rust staining
Raw Umber / Brown - old rust staining
Black - overall wash to tone down, blend and add soot / dirt, shadow effect to bring out the overall detail