Will Small Scratches on the Car Body That Expose the Primer Rust?
2 Answers
Generally, any scratch on a car has the potential to rust, and if the primer is damaged, the likelihood and speed of rusting will increase further. Here is some additional information: 1. Car paint typically consists of four layers, from the inside out: the electrophoretic layer (primer), the middle coat, the color coat, and the clear coat. The so-called "primer" is actually a protective film applied to the metal body through an electrophoretic chemical process, primarily to enhance the body's corrosion resistance. Typically, white cars have black or gray primer, while dark-colored cars have the opposite. 2. The middle coat is sandwiched between the primer and the color coat, serving to bond them together, ensuring the color coat adheres more uniformly and firmly to the surface, enhancing the paint's fullness. The color coat is the layer that gives the car its visible color. The clear coat is transparent and colorless, serving to increase the paint's glossiness and protect the color coat from scratches. There are two types of color coat processes: 1k and 2k. The 2k process includes a built-in protective layer, eliminating the need for a clear coat.
If small scratches on the car body expose the primer, rusting is indeed possible because the primer acts like a protective layer for the metal. Once it's scratched, the metal is directly exposed to air. Especially in humid weather or rainy conditions, moisture and oxygen can easily react with the iron, gradually forming rust spots. I've seen many cars where a small white spot initially turns into a patch of rust within months, and in severe cases, it can even cause the paint to peel. If not treated promptly, deep rust can affect the structural strength of the car body, particularly in thinner areas like around the doors or wheel hubs, potentially leading to perforation. I recommend car owners not to wait—once they notice scratches exposing the primer, they should clean them with rust remover paste, then apply touch-up paint or visit a professional shop for a respray. During each car wash, it's good practice to inspect the body and dry any moisture with a soft cloth, which significantly reduces the risk of rust. Keeping the car clean and dry is key—don’t let a small issue turn into a big problem.
