How to Prepare Metal Surfaces for Painting

It's important to properly prepare metal surfaces for painting.

Metal surfaces can look brand new with a touch of new paint. Don't think of painting anything metal until you properly prepare the surface, however, or your creative streak will only make a mess. Paint will not stay on galvanized steel, tin or aluminum that is not properly cleaned and prepared.

Things You'll Need

• Mineral spirits
• Rags
• Commercial rust remover
• Sandpaper
• Wire brush
• Metal primer

Instructions

1. Clean the surface of new metal with mineral spirits which is available at any hardware, paint or department store. This will remove all traces of oil and grease left on by the manufacturing process. Galvanized steel -- such as that used in gutters -- has to weather about six months before it's safe to paint, otherwise the paint will come off very quickly.

2. Apply a commercial rust remover according to directions if there are any signs of rust on the surface. Paint will not adhere to rust. Even a little bit will ruin the whole project, so don't skip this step.

3. Sand the surface starting with a coarse grade sandpaper or a wire brush -- you can use a wire brush attachment on a drill as well. Sand again with a finer grit sandpaper, and finish the sanding with a 240 grit sandpaper. Wipe with a damp rag to remove all traces of dust.

4. Prime the surface with a primer made specifically for metals. You can find these at most paint and hardware stores and all businesses that cater to the industrial market. Now your metal surface is ready for painting. Be sure to use paint that is specifically formulated for metal.

Tips & Warnings

• Make sure metal surfaces are really clean before you prime or paint.

• Don't paint galvanized steel until it has weathered for six months!

References

• Mar-K Quality Parts: Preparing Parts for Painting
• Golden Glow Paints: Surface Preparation Guide