I did encounter some difficulty in replicating the blueish worn steel look but I discovered completely by accident a cool trick. The metal I was dealing with is a combo of all sorts of metals...not steel. My whole goal was to try to get the steel look so I went and bought 3 types of blackening/blueing agents. 2 were the Permablue oxides. A Aluminum oxide and a steel oxide. Then i bought a bottle of blacken it. Like a mad scientist I began layering all 3 types of oxides on the metal. After many coats and some steel wool I got the look I wanted. It was neat watching the metal turn blue or black and sometimes brown but the effect was achieved.
On the Covers and housing all I did was use good ole fashion Rustoleum Semigloss paint on BARE metal. No primer. As long as you prep the metal ie. sand and wash it it will stick great. No flaking.
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