To get a great-looking car paint job, you need to prepare the surface properly. Here are the steps you need to take to get your vehicle ready for painting.

Wash the car

Washing your car before painting helps dissolve and remove dirt and other substances that can contaminate paint. Use car wash soap, not dish or laundry soap. While dish soap dissolves food and cooking residue and laundry soap removes stains from fabric, car soap is specifically made to clean away contaminants on cars, such as tree sap, brake dust, and road grime.

Wipe the car with solvent

Cleaning your car with a solvent such as GLM-900 Wax & Grease Remover will remove surface contaminants from the old paint. Solvents make contaminants float to the top of the surface so you can wipe them away, leaving a nice, clean surface. The finish will adhere to that clean surface, reducing the chance of flaws in your final finish. 

There are two types of solvents. One is petroleum distillate, such as the GLM-900 Wax & Grease Remover and the other is alcohol-based such as GLM-800 Pre-Paint Cleaner

Sand the car

Thoroughly sanding your car surface is necessary so your new finish adheres to your vehicle.

The most common sandpaper used on cars is made from silicon carbide abrasive. While silicon carbide doesn’t last very long, it’s suitable for quickly removing the old paint finish.  This sandpaper comes in various grit grades.

Once you are finished sanding, re-wipe the surface with GLM-800 Pre-Paint Cleaner to get rid of any sand shavings and handprints. Wipe off the GLM-800 Pre-Paint Cleaner while it is wet, using a clean rag.

Mask the car

It’s important to use the right tape and paper when masking your car for painting. If you use butcher paper or newspaper, the solvent will seep through. The best car masking papers are coated on one side with either wax or plastic to prevent solvent from seeping through them.

Automotive masking tapes are also treated to prevent solvent from penetrating them. Good masking tapes use special adhesives that will hold tight during painting, but then release cleanly, even after a high-temperature bake.

Tack wipe

Before you prime your vehicle, use a tack cloth to wipe down and remove any dust particles. Tack rags are generally made from cheesecloth and coated with shellac. Unfold the tack cloth to its full size so the cloth collects and holds more dust, and it will be less likely to leave tracks in the basecoat. 

Be sure you tack off your entire vehicle, not just the panel to be painted, but also the masking paper surrounding the repair and even the air hose of the paint gun.

Prime

You want to use a good primer gun to apply the primer. Primer can be expensive, so it makes sense to use a good primer gun with a 1.8 tip. For best results, use GLM-2000 Urethane High Build Primer (two-component), which will not shrink and swell the way a single-component primer often does.

Block sand

Once the primer is applied, the last step in preparing the surface is to sand it until it’s perfectly smooth. Block sanding by hand can be done on the smaller, odd-shaped areas of the car. Use power sanders in the right shapes and sizes on other areas of the vehicle. When you’re finished sanding, lightly wipe the car once again with GLM-800 Pre-Paint Cleaner, using a clean rag.

Following these steps will prepare your car for a great paint job.