How to Prepare for Car Painting
One of the most important aspects of car painting is the preparation process. Although the application of a good topcoat is vital to the success of a paintwork project, your final layers of paint will only be as good as the preparation that has taken place previously. This article explores some of the most common vehicle preparation techniques available.
Tip #1 – Repairs
Repairs to a vehicle panel are an important part of producing a good quality paint job and the removal of dents is one of the first steps to success.
Begin by sanding around the dents using a random orbital sander and a P120 sanding disc. Make sure that the old paint in keyed approximately four inches past the dent itself.
Apply a light, even coat of body filler and allow to dry. Take your sanding block and a sheet of P120 paper and gently rub down the filler until a smooth, flat surface is achieved. Finish the filler with P240 or P320 paper so that excessive scratches in the filler are removed.
Tip #2 – Panel Preparation
Once the repairs are completed, take your random orbital sander and a P320 discs and feather out the edges of paint around the filler to ensure a totally flat surface. Be sure to remove any scratches or imperfections in the paintwork during this stage. The remainder of the panel can be keyed using P800 wet-and-dry paper or a fine grade scotchbrite. Use compressed air to blow the dust of the panel and wipe clean using degreaser and lint-free cloth.
Tip #3 – Priming and Flatting
Rough mask the panel around the edges of the filler and paper back to prevent overspray landing on adjacent panels. Using a good quality high-build primer, apply three generous coats and allow to dry thoroughly. Most primers take around 6 hours to cure at room temperature.
Once the primer has cured, take a rubber sanding block and a sheet of P800 wet-and-dry paper and rub down the primer thoroughly. Use your hands to feel the repair to make sure it is entirely flat and double check for any deep scratches that may need removing prior to the painting process.
Tip #4 – Clean and Mask
Blow off any excessive dust using compressed air and degrease the panel again. It is important to clean panels regularly during the preparation process so that all traces of grease or sweat are removed.
Use a good quality tape to accurately mask off the entire panel and sheet back with paper. You may wish to cover the entire vehicle with polythene sheeting prior to painting to prevent overspray landing on other panels.
Tip #5 – Final Clean
The vehicle should be degreased one last time before painting begins. Use two new pieces of lint-free cloth and degreaser and make sure that all traces of solvent are removed from the panel. Once complete, take a tack-cloth and gently wipe over the entire panels so that the stick residue of the pad removes any last traces of dust.
The vehicle is now ready to paint. Don't forget to use suitable protective respiratory equipment during the painting process.