I have a design that requires the use of brass (No. 360 copper alloy). This design requires that some portions be painted (epoxy primed and polyurethane topcoated). I have no experience painting brass and/or know if this alloy is even “paintable.” Could you provide some insight into this matter and recommend how to best prepare the surface for painting? P.S.
Painting brass is as easy as painting anything else, if the surface is properly prepared. Brass and other alloys of copper will corrode. The corrosion products may be tightly or loosely adherent to the surface. In either event, they must be removed by some pretreatment process before painting.
As with any substrate the first step in pretreating brass is to clean it to remove oily soils and other foreign materials. The next step is to remove any corrosion products. This is done by abrading using sandpaper, brushes or blasting with abrasive media; by etching using an acid such as a bright dipping solution; or by applying a chromate pretreatment.
I recommend you apply the epoxy primer as soon as possible after pretreatment. After priming and curing, the polyurethane topcoat can be applied.