You are likely familiar with the liquid paint that you would apply to a wall or fence, but there is a second type of paint used on many steel products. Steel is often colored with powder coatings. Though this coating is thicker and more durable than liquid paint, if you want to paint a different color over it, it can be difficult to get the liquid paint to adhere. Below are some steps to painting over powder coated steel.
Preparing the Steel
The coating will likely be very smooth, so you will need to sand it so it is rougher and so the paint will more easily adhere to it. Use 220-grit sandpaper. The process will leave behind residue that you will need to wipe off with a cloth. Then, rinse the coating and allow it to dry. You must remove all of the dirt, grease and dust so that the paint adheres to the steel properly. A power washer with 900 psi or higher might be necessary to wash the steel properly.
Picking Your Paint
Choose a paint that is solvent-based. Enamel is often one of the best options because it is not expensive, comes in a variety of colors, and will adhere well to the primer. Epoxy paints are even more likely to stick, but they are more expensive and have fewer color options.
Applying a Primer
Prepare a primer that is designed to be used with steel. Use some of the primer to make sure the steel has been sanded well enough to allow for the paint to adhere. If the primer does not adhere to the steel, wipe off the primer and return to the sanding process. When the primer does adhere to the steel, apply the entire product with a single coat. Then, you will need to determine how you will apply the rest of the paint.
Using a Sprayer
A sprayer is the easiest way to apply paint to uneven surfaces. However, you will need to make sure that the area is well ventilated. Apply the paint in several thin layers to reduce the risk of the paint dripping.
Using a Roller and Brush
Apply the paint the same way you would apply it to a wall using a roller. Cover the entire object with paint and then use a synthetic paintbrush to reach areas that the roller cannot reach. Apply the paint using very smooth strokes. Try to brush with the grain. After the paint has dried, you'll finally have the color you wanted.