1. Not removing dirt and wax before paint touch-up
Applying touch-up paint on top of a dirty surface will prevent it from adhering properly. First, you need to wash it with water and some dish soap. Next, follow it up with prep solvent.
The prep solvent removes oils, road grease, dirt, car wax, and other surface contaminants and also improves adhesion to the surface.
2. Painting in the wrong temperatures
Painting your car in temperatures lower than 55F or higher than 80F is not a good idea. As the weather gets colder or hotter, the behavior of the paint changes which might result in blotches or blushing, bubbling discoloration, or a gritty texture. The ideal temperature is 72F with 50% humidity.
3. Using the wrong sandpaper
You need to use sandpaper specially designed for car paint repairs. Regular wood sandpaper or sanding block is too rough and will leave scratches. If you want to do wet sanding, make sure it says wet/dry on the label.
4. Not applying primer
You need to apply primer because paint doesn’t stick very well to bare metal. Primer ensures better adhesion of paint to the surface, increases paint durability, and provides additional protection for the material being painted. If you don’t apply primer, your paint will start chipping after a while.
5. Using paint older than 6 months
Make sure you are using a fresh touch-up paint for the best result. Using old paint might result in paint cracking and chipping.
6. Applying paint layers all at once
Not giving each layer enough drying time might result in a paint bubble, because the top layer dries faster than the bottom layers. Drying time varies from 30 min to 1 hour depending on the product and the temperature.
7. Using a nail polish instead of a clear coat
This might sound like a great idea, but in reality, nail products last only for 1 or 2 weeks. It’s completely different from the auto clear coat that is designed specifically for car paint protection.
8. Using bath towel or paper towel on the car surface
Wood fibers of the paper products are too rough and will leave scratches. I strongly recommend using Microfiber cloth because it is super soft with threads that are 100 times finer than human hair. The super absorbent weaves hold up to seven times its own weight in fluid and will not scratch paint or plastic.
9. Applying wax right after painting
You need to wait at least 30 days before applying wax. The idea is not to apply any substance that creates a barrier coating over the surface that could “potentially” lock or seal in the solvents and prevent them from out-gassing or evaporating.
Solvents, also called thinners and reducers, are used to thin the paint down so that it can be atomized into a spray when applied with a paint gun using compressed air. In other words, the paint needs 30 days to dry completely, and applying wax will keep it from happening.
10. Allowing rust to develop
I recommend repairing car scratches or chips as soon as possible. When bare metal is exposed to moisture and air, rust starts to develop. If not repaired, it will continue to spread until holes form in a car’s metal frame. You can get rid of it with good quality rust remover.