I use 3" x 3" x 0.25" mild steel square tubing to build my CNC machine. I need to make sure I protect it from rust. I will be using a 4.5" wire grinder attachment to remove the rust already on the metal. What is the best way to stop future rust? I know I can buy the Rust-Oleum clean metal primer. Is there a better method and how many coats should I apply? I plan to spray some color over the primer. Any suggestions on what color I should use? Should I use dark colors (black, dark grey) or lighter colors (yellow, white, blue).
Thanks,