What is the main purpose of using body fillers in collision repair?

The primary purpose of using body fillers in collision repair is to restore the original shape of a panel after repairs and to smooth out surface imperfections. Body fillers, often made from materials like polyester resin, are applied to damaged areas to fill dents, scratches, and other imperfections. Once applied and cured, these fillers can be sanded and shaped to match the original contours of the vehicle, ensuring a smooth surface that is ready for painting.

Replacing damaged panels entirely is typically reserved for more severe damage where repairs cannot restore the integrity of the structure. While fillers can offer some protection against rust due to their sealing properties, that is not their primary function. Enhancing paint adhesion is a secondary benefit provided when surfaces are properly prepared with body fillers, but the core purpose remains the restoration of shape and smoothness. Therefore, using body fillers is essential for achieving a high-quality finish and restoring the aesthetics and integrity of the vehicle’s body.