How to Perform Paintless Dent Repair on a Car?
4 Answers
The methods for paintless dent repair on a car are as follows: 1. For relatively shallow scratches or stains, you can use an eraser, toothpaste, or essential balm to remove minor scratches on the car body. 2. For small, slight dents on plastic body panels, you can use a lighter with aluminum foil or a hairdryer to heat the area until it softens, then push it out from the inside with your fingers. Alternatively, pouring boiling water over the area can achieve the same effect. A hairdryer is also suitable for larger dents on plastic, aluminum, or metal body panels. 3. For larger dents, you can use a plunger coated with Vaseline around the edges, place it over the dent, and pull it out with force.
I've been in auto detailing for nearly twenty years and have seen all kinds of dent repairs. The core of paintless dent repair relies on physical methods to either pull out or push back the dent. There are plenty of tools for the job: for small dents, we use a hot glue gun to attach a specialized pull hammer, pulling it out like cupping therapy; for complex structural dents, we use pry bars with different curvatures to slowly push from inside the panel gaps. The key is assessing the extent of steel panel stretching—overstretched areas need to be hammered flat and then heat-treated before finishing. After repair, a reflection meter checks for even paint refraction—inexperienced technicians often leave subtle marks on the factory paint. My advice: a fingernail-sized dent costs around 300 yuan, but if it's on body creases or headlight corners, the price doubles and perfection isn’t guaranteed.
Last time my car door got a dent the size of a dimple when the neighbor's car door hit it, the repair shop guy used this amazing method! He took this tool that looked like an oversized suction cup, first used an infrared lamp to heat the dent for two minutes to soften the paint, then slapped the suction cup on and quickly pulled it off. After repeating this five times, the dent popped right out. Later I learned this is called the glue pull method—it doesn't damage the original paint and works especially well on aluminum alloy bodies. Nowadays some high-end shops even have dent repair robots with camera-equipped robotic arms that reach inside the door panel to push out the steel sheet with precision up to 0.1mm. But heads up—don't expect seamless repairs on double-layered steel areas like rear quarter panels; you'd need to remove interior trim panels for those.
The principle is essentially thermal expansion and contraction combined with molecular memory. The technician heats the dent to around 60°C with a heat lamp, then quickly applies tools when the metal's ductility increases. Currently, there are three mainstream methods: magnetic pull for iron car bodies, glue-pull which is versatile but leaves adhesive marks, and an internal lever method requiring special tools inserted into body gaps. The key is observing the dent's edge curvature—sharp angles are ten times harder to repair than smooth curves. Never use those DIY dent pullers bought online—my cousin once tore off a large patch of paint. Factory paint has a self-healing layer, but repainted vehicles can't achieve markless repairs.
