I have looked at paints in a couple of hardware stores and have not found any primers that say "self etching". Many say for metal, but don't mention self etching, and claim "rust" preventatives, so suspect they are just for steel. I can get zinc chromate (green stuff) from a marine store, but rather expensive. Surfing Krylon and Rustoleum websites hasn't helped, outside of showing a pic of what the hardware stores didn't have. . Anyone find a reasonable self-etch primer? Does most Wally Worlds carry it?