Bondo body filler is the quickest way to fix dents, dings and small rust spots on a car before paint. The steps are simple: sand to bare metal, mix the filler with hardener, spread thin layers, then sand and prime. The details are what decide whether the repair stays invisible. This guide covers which Bondo product to use, the right mix, and the sanding grits that give a smooth, paint-ready finish. Which Bondo Product Do You Need? Job Product Ready to sand Dents and dings, general bodywor …