Sheet metal painting is a kind of automobile repair technology, which mainly repairs the deformed part of automobile metal shell. For example, if the car body shell is knocked out of a pit, it can be restored to its original state by sheet metal, and then the deformed car metal surface can be restored to the same brightness as other intact places by spraying special paint. However, after the automobile body is corrected by sheet metal, there are still some defects that cannot be compensated by sheet metal work. Even if new parts are replaced, there will be imperfections. In order to be more perfect and accurate, we must make up for the defects through sculpture technology. After the car is damaged due to deformation and other reasons, its flatness, wheel angle and lines need to be scraped and polished.