Why is the car paint cracking?

[LeMaximus]

If corrosive substances such as bird droppings or tree sap adhere to the car and are not removed for a long time, exposure to high temperatures in summer can cause the car paint to crack. Here is some relevant information about car paint: 1. Introduction: Car paint is a protective film sprayed onto the car, a type of coating that makes the car body less susceptible to corrosion and also provides an aesthetic appeal, with different car paints offering different effects. 2. Advantages: The main characteristics of car paint include excellent film fullness, high gloss, high hardness, good adhesion, superior mechanical properties of the paint film, outstanding gloss retention, weather resistance, and wear resistance, as well as good resistance to acids, alkalis, alcohol, and gasoline.

[MacEverly]

I have quite some experience with car paint cracking, mainly three common situations. First is paint aging, especially for cars over five years old. Constant exposure to sunlight combined with winter freezing and summer heat causes the paint surface to gradually develop fine cracks that eventually split open. Second is poor-quality touch-up paint. If you had a scratch before and just sprayed on some cheap paint, the lack of adhesion can cause it to peel and crack. Third is collision damage. Don’t think minor scrapes are harmless, especially on stressed areas like the hood and fenders. A small white spot from a stone chip can develop into spiderweb-like cracks over time. If you notice cracking, it’s best to deal with it promptly. First, use clear nail polish to temporarily seal the crack to prevent moisture from seeping into the metal and causing rust. Then, find a reliable auto body shop to sand down the entire affected area and repaint it properly. Never try to cover it up with a touch-up pen—that will only make the cracks more obvious.

[VonNolan]

I reckon paint cracks are mostly due to improper maintenance. Leaving the car parked outdoors all summer exposes it to UV rays and high temperatures, which can make the paint brittle within two years. Car washes can be problematic too – those roadside stalls often use strong alkaline detergents that severely damage the paint. While the car may look shiny afterward, these cleaners actually corrode the protective layer. Incorrect waxing methods also contribute; applying wax without thoroughly cleaning the surface first traps dust particles beneath the wax layer, causing friction that inevitably leads to cracks over time. If you notice fine cracks, don't panic. If only the clear coat is affected, gently sand with 2000-grit wet sandpaper and apply a color enhancer to restore it. However, if the primer is exposed, it's best to repaint the entire panel – spot repairs will show color differences within six months. For prevention, park in underground garages whenever possible, use pH-neutral car wash solutions, and apply a silicone-based sealant wax quarterly.

[Millard]

Temperature fluctuations are a killer for car paint, especially in northern winters where it drops to minus twenty degrees Celsius. Parking in a garage at noon and outdoors at night, with just a few cycles of hot and cold, the paint can't hold up. My previous white car had cracks near the door handles that looked like a tortoise shell, all due to temperature changes. Additionally, flying gravel while driving is more damaging than you'd think. A pebble the size of a fingernail hitting the car door at high speed can crack the surrounding paint with its impact. For prevention, a car cover is the most effective; a PVC cover costing around two thousand can last five years. When it comes to repairs, be cautious: dealerships often recommend repainting the entire panel, but for a crack the size of a palm, spot repair technology can fix it at half the cost without damaging the original factory paint.