Body Filler

🔧 What is Body Filler?

Body filler, often referred to by brand names like Bondo, is a two-part polyester resin product used to fill dents, dings, and imperfections in automotive body panels. It hardens quickly after mixing with a catalyst (hardener) and can be sanded smooth for a flawless finish before painting.

✅ Benefits of Using Body Filler

1. Restores Smooth Surface – Ideal for fixing dents, dings, and small holes.

2. Paint Ready – Accepts primer and paint well for seamless repairs.

3. Fast Curing – Most fillers harden within 15–30 minutes after application.

4. Strong Bond – Adheres well to metal, fiberglass, and even wood in some cases.

5. Customizable – Can be shaped and sanded to match curves and contours.

🛠️ Use Process (Step-by-Step)

1. Surface Prep

   • Sand the area with 80-grit sandpaper to remove paint and rust.

   • Clean with wax and grease remover to ensure proper adhesion.

2. Mixing

   • Place a golf ball–sized amount of filler on a non-porous mixing board.

   • Add a small ribbon (pea-sized) of hardener.

   • Mix thoroughly until the color is uniform (usually a light pink or beige).

3. Application

   • Use a plastic spreader to apply filler in thin, even layers.

   • Avoid over-application—multiple thin coats are better than one thick one.

4. Curing

   • Let it cure for 15–30 minutes until it’s no longer tacky and is fully hardened.

5. Shaping and Sanding

   • Start sanding with 80-grit to shape.

   • Progress to 180–220 grit for smoothing.

   • Feather the edges into surrounding areas.

6. Finishing

   • Apply a glazing putty for pinholes or minor imperfections if needed.

   • Sand again and finish with primer and paint.