Should the Original Paint Be Sanded Off Before Repainting?
2 Answers
Repainting requires sanding off the original paint. The reasons are as follows: 1. The repainted area will increase the thickness of the paint film. If the original paint is not removed, the repainted area will be higher than the surface of the original paint. Generally, the entire clear coat is sanded off, followed by the application of the base coat and then the clear coat. 2. If the original paint is not removed, the new paint and old paint may separate and peel after blending. 3. If the original paint is not treated, even if the new paint looks good initially, it can easily peel off during car washing. 4. If the original paint is not removed, color differences may occur.
I've handled paint repairs on several cars before, and I find this question very practical. Whether you need to sand off the original paint depends on the condition of the original paint and the type of paint job you're planning. If the original paint is generally intact, without peeling or rust, you don't need to remove it entirely. Just lightly sand the surface with sandpaper to remove gloss and impurities, ensuring better adhesion for the new paint. This is called 'surface preparation,' and it's a crucial step. Skipping it might make the new paint look smooth initially, but it could soon bubble or peel due to dirt or grease blocking adhesion. However, if the original paint is cracked, rusted, or has deep scratches, you must sand it off completely. Otherwise, the new paint won't properly cover the problem areas, leading to recurring issues after the repair. From experience, I always take the time to perform an adhesion test: first, try a small area with tools to check how well the new paint sticks. After painting, cleaning and sealing are essential to ensure long-term aesthetics and durability. Don't cut corners here; investing a few minutes in this step saves future trouble.
