It’s no secret your car’s interior often takes as much of a beating as its exterior. Exposure to UV rays, extreme temperatures, and ‘family-induced environmental catastrophes’ all take their toll on its mostly plastic surfaces. Cleaning and conditioning can only go so far. At some point, you have to actually restore interior trim if you want to save it.
Thankfully, restoring interior finishes is a simple and affordable project for most DIYers. Depending on what you’re restoring, you may even be able to restore the finish in place without removing the part. And you typically don’t need any special equipment, just some good cleaning supplies, a clean workspace, and the right materials.
The last item on this list is important. It’s true that most paints will generally stick to most clean surfaces. However, you really need to ensure you’re using a finish designed specifically to bond with polymers used in interior plastics. These can include variations of polypropylene (PP), polyethylene (PE), polycarbonate (PC), polyvinyl chloride (PVC), and others.
A number of companies produce special paints designed just for interior finishes. These paints bond to properly prepared plastics and remain pliable after application to prevent flaking or peeling. They’re also available pre-mixed to match not only the colors of many factory finishes, but also the correct sheen. These include SEM Color Coat, Dupli-Color Vinyl & Fabric, and Color Bond LVP.
To demonstrate the process to restore interior plastic, we used the dashboard panel out of one of our project vehicles. Its finish was showing mild fading, but more obvious were several locations where the surface was scratched or scuffed. As part of the overall restoration process, we also want to ensure this vehicle’s entire interior matches. We’re using this finish to unify all the different parts that have aged and faded differently over three decades.
Process to Restore Interior Plastic
Clean
Start by cleaning the entire area to be painted with a mild detergent or car wash solution and a soft brush. We used a clean nylon detailing brush with firm bristles to clean deep into the texture without damaging it. Rinse thoroughly to remove any soap residue and dry completely, using compressed air if necessary.
Scuff
To open up the surface of the plastic without removing its texture, use a mild body shop scuff pad. Often called hand pads, the least abrasive grade is typically gray in color. The goal is to lightly abrade the entire surface for better adhesion, especially on smoother surfaces.
Prep
Wipe or blow off any dust residue from the scuffing process, ensuring it’s removed from all corners and crevices. Use a prep solvent, such as Eastwood Pre, and a clean, lint-free towel to give the surface a final cleaning. This will remove any oils remaining near the surface, including silicone-based plastic conditioners or trim dressings that might impede adhesion.
Spray
Apply paint evenly to the plastic trim in light coats according to the manufacturer’s instructions. These finishes tend to be thin, allowing them to flow into fine textures without burying them in buildup. As such, they run easily if over-applied.
It’s best to apply several light mists of color, allowing time for each layer to tack before applying the next. This method will also prevent the final finish from looking too shiny.
Dry
Most interior plastic paints are air-drying finishes, but they also tend to be slow to dry to their final finish. Allow the part to cure in a clean, dry area for at least a day to prevent marking or otherwise damaging the surface. Once it’s thoroughly dried, you can review it for coverage and touch up any thin spots or inconsistencies.
