What are the techniques for applying body filler?

[AylaFitz]

Techniques for applying body filler on cars are as follows: 1. When applying filler, large dents can be filled in stages—first fill the major depressions, then gradually level them. 2. For the initial sanding, always use the coarsest sandpaper and sand horizontally, using plenty of water to achieve a generally smooth surface. 3. If small dents remain, apply more filler and sand again with coarse sandpaper. Repeat until the entire surface is smooth with only sanding marks visible. 4. Next, apply a thin finishing layer of filler, which must be very fine, then sand it smooth with appropriate sandpaper. 5. There are many types of fillers with different functions, and the compatibility requirements of coating materials make selecting the right filler particularly important.