Is it necessary to repair scratched car undercoating?

[McHeidi]

It is not necessary to repair the scratched undercoating of a car. Here is the relevant information: 1. The difference between original factory paint and repair paint: Both can meet the decorative and anti-corrosion requirements of the car surface, but the construction methods differ greatly. Original factory paint now uses robotic arms for automatic coating, so the viscosity and other indicators of the paint are generally fixed, resulting in high-quality original coating. Repair paint, however, is mostly applied manually, and the coating environment is far inferior to that of the original factory. Therefore, after car paint repair, the quality of the paint film is usually somewhat compromised. Repaired paint is not as good as original factory paint and is prone to fading and flaking, with some areas showing color differences after repair. 2. Repair methods: Large scratches cannot be fixed with car wax. If immediate paint repair is not possible, use toothpaste to cover the scratch to prevent rust. If you have a touch-up pen, use it to repair the scratch by applying it evenly around the area. After the paint dries, reapply car wax to easily remove any residue.

[VictoriaDella]

As a mechanic with over a decade of experience, I must emphasize that scratched underbody paint must be repaired. The chassis is the skeletal structure of a vehicle, and that layer of paint primarily serves as anti-rust protection. Once scratched, exposed metal can rust extremely quickly when exposed to rainwater or humid air. What may start as a small spot can spread, compromising the metal's strength. Over time, this can affect suspension components, steering systems, and even the entire frame's safety. I've seen countless cases where owners neglected this issue and ended up paying for major repairs. Especially if you drive a new car or live in rainy coastal areas, timely treatment can prevent big headaches. I recommend first assessing the scratch size - minor ones can be touched up with anti-rust paint yourself; for serious damage, it's best to visit a professional shop for complete rust removal and repainting. Prevention is always better than costly repairs later. Don't assume that just because the underbody isn't visible, it doesn't matter - small oversights can lead to major problems.

[GraceDella]

As an ordinary office worker, last year during an outing, I scraped the curb and damaged the chassis paint. Initially, I thought it was a minor issue and ignored it. A few months later, I noticed a creaking sound from the chassis, which worsened on rainy days. After repairing the car, I realized the rust had spread, costing me thousands. I deeply regret trying to save a little money initially but ending up spending much more. So, my lesson is: chassis paint damage must be addressed promptly—delaying can be costly. It affects the car's lifespan and driving safety; for example, rust can impact brake stability. For minor damage, you can simply wash the car and apply some rust inhibitor as a cheap fix, but serious damage requires professional attention. Depending on the car's age, minor scratches on an older car might be manageable, but new cars must be repaired early—don’t take it lightly.

[IsabelleMarie]

As a car enthusiast, I always emphasize chassis maintenance. That layer of paint isn't just decorative—it's crucial for moisture isolation and corrosion prevention. Once scraped off, the metal becomes prone to rust, eroding the chassis structure and accelerating aging. Proper repair can extend your car's lifespan by five to ten years without issue. DIY solutions cost as little as ten yuan for anti-rust spray application, while professional repairs run a few hundred yuan—both options save money and hassle in the long run. Neglecting this can depreciate your vehicle's value and impair performance, potentially affecting suspension and safety systems. Regular chassis inspections with simple rinsing followed by touch-up painting are key preventive measures. New cars deserve particular attention, but older vehicles shouldn't be overlooked either—proactive care avoids costly major repairs later.