Can I spray paint over rust?
Yes, you can spray paint over rust. Before you paint, take the time to prepare your surface properly. Surface preparation is extremely important and is the best predictor of how long your new paint finish will last.
Remove Loose Rust and Paint
Remove loose rust with a wire brush, sandpaper or chemical rust remover. The goal is to make your surface as smooth as possible to ensure the new paint finish adheres well to the surface.
If your surface has any chipped or peeling paint, remove all loose paint. Lightly sand glossy surfaces to dull the finish. Do not sand old paint that may contain lead. For more information, contact the National Lead Information Hotline at 1-800-424-LEAD.
Dirt, grease and oil can also affect paint adhesion, just like loose rust and peeling paint. Ordinary soap and water or household cleaner is effective at removing most surface grime. Remove grease and oils with a degreaser or denatured alcohol. Avoid using strong solvents on previously painted surfaces. Solvents may soften the old paint, which can then cause the new paint to wrinkle or pull away from the surface. Rinse and let your surface dry completely.
Your surface should now be clean, dull and dry.
When surface has extensive rust
If the surface still has extensive rust after all loose rust has been removed, start with Krylon® Rust Protector™ Rust Converting Primer or Krylon® Rust Tough® Rust Fix. This primer chemically changes rust into a waterproof, paintable surface. Spray directly over the remaining rust to protect against further corrosion. Apply multiple thin coats to prevent runs and drips. This primer sprays on clear and dries to a black primer finish. After 24 hours, topcoat with your choice of paint color. Surface can be sanded lightly before applying topcoat, if desired.
When surface has some rust
If the surface still has some rust after all loose rust has been removed, spray with Krylon® Rust Protector™ Rusty Metal Primer. This primer offers increased corrosion protection for rusted surfaces and superior adhesion and hiding. Apply multiple thin coats to prevent runs and drips. The primer dries to the touch in 8 minutes and tack free in 15 minutes. Topcoat with your choice of paint color.
When surface rust has all been removed
If you were able to remove all traces of rust with a wire brush or sandpaper, you can either prime with Krylon® Rust Protector™ Rust Preventative Primer or Krylon® Rust Tough® Enamel Primer, or you can choose to skip the priming step because Krylon Rust Protector and Rust Tough Enamels are specially formulated to offer superior rust protection direct to metal – even without a primer.
Priming always helps to create a smooth, consistent surface that is ideal for painting. Primer also helps decrease the likelihood of color change and increases adhesion. If you choose to prime, apply multiple thin coats to prevent runs and drips. Rust Protector Primer dries to the touch in 8 minutes, tack free in 15 minutes and a topcoat can be applied at any time. Rust Tough Primer dries to the touch in 20 minutes and a topcoat can be applied after 30 minutes.
After your surface is clean, dull, dry and primed appropriately, spray Krylon Rust Protector or Rust Tough Enamel on your well-prepared surface. Apply multiple thin coats to prevent runs and drips. Dries to the touch in 8 minutes and tack free in 15 minutes.
Still have questions on how to spray paint over rust? Ask Krylon.