
Depending on the condition of the car, this process usually takes only 30 to 40 minutes. With the naked eye, white cars typically have black or gray primer, while dark-colored cars show the opposite. Below is some information about vehicle painting: 1. Causes: Rainwater generally contains acidity, and acid rain can significantly damage car paint, leading to oxidation of the paint surface and loss of gloss. 2. Consequences: After rain, the increased humidity affects the drying speed of freshly painted surfaces, but the moisture also reduces dust in the air, which is beneficial for painting. 3. Precautions: (1) If the car has just been painted, avoid exposing the newly painted areas to water and dust; (2) It's best not to drive the car out on rainy days, as the fresh paint is still delicate and can be marked by rainwater, leaving unsightly traces that may not be removable even with polishing. Parking in a garage at night is recommended; (3) Sunlight is not a concern—it only speeds up the drying process and is beneficial; (4) Avoid exposing the newly painted areas to chemicals and oil stains.

I always take great care of my car. When I notice a scratch, I immediately squat down and examine it from different angles. It's most visible when viewed against sunlight – if the scratch appears whitish, it's on the clear coat; if it shows gray, it's reached the colored paint layer. The worst scenario is when the scratch edges turn yellowish with rust spots – that definitely means it's penetrated the primer. Here's a little trick: wet your finger and swipe it across the scratch – where the water trail breaks is roughly the deepest point. Light scratches can be fixed with scratch wax, while deeper ones require touch-up paint. Last time when a branch left white lines on my door, I used polishing compound and they became invisible after just three minutes of rubbing. Remember to use a soft cloth and polish in circular motions to avoid damaging the paint.

Judging the depth of a scratch is actually quite simple. Gently run your fingers over it. If you can barely feel any unevenness, it's likely just in the clear coat. If you can clearly feel a groove, that's more concerning. In this case, use your fingernail to scrape across the scratch horizontally: if your nail catches and turns white, it means the scratch has penetrated the color coat. I usually carry a flashlight to inspect scratches – under light, the reflection from the metal base is quite obvious. Recently, I discovered a handy tool called a scratch detection pen. It's a UV pen that costs around twenty yuan. When you shine it on the scratch, different depths show different colors, which is much more accurate than judging by eye.

Car paint is like a sandwich: the top layer is the clear coat, the middle layer is the color coat, and the bottom layer is the putty and steel plate. Light scratches only damage the clear coat, appearing as thin white lines; moderate scratches reveal the colored marks of the base color coat; the most severe ones expose the black or metal base material, which can oxidize and rust. Repair suggestions: polishing is enough for the clear coat, touch-up pens are needed for color coat scratches, and exposed metal base material requires panel beating and repainting. Remember to dry the car immediately after rain, as acid rain can corrode the edges of scratches.


