Vehicle Body Preparation Best Practice

Sometimes a vehicle has been in a collision so bad that it requires body filler to level a significant dent or crease in the vehicle panel. First, the dent needs to be extracted out of the metal using an external tool. Then, you can follow the steps below for the best practice in body preparation:



Clean the Repair Area

Begin by washing the area with soap and water then use a wax and grease remover. Wipe the vehicle dry with a clean cloth.

Best Practices - Body Preparation - Step 1


Grind the Repair Area

Prepare areas to provide tooth for the filler/putty/glaze with 36 to 50 grit sandpaper and a disc sander tool then blow off debris with clean, dry air.

Best Practices - Body Preparation - Step 2


Prep for Filler

Sand the repair area with a Dual Action (DA) sander using 80 grit sandpaper. Remove any debris with clean, dry air. The objective is to round off the coarse grit scratch on the bare metal to prevent bridging. This will eliminate primer sinking into scratches and reduce pinholes. It will also prepare the paint edge to receive putty or glaze.Try to straighten the metal as necessary prior to applying filler.

Best Practices - Body Preparation - Step 3


Apply Body Filler

Mix body filler on a non-porous mixing board using recommended hardener ratio. Slice and fold in the hardener, be careful not to stir or flip too rapidly. Apply filler to the panel being careful to keep the body filler within the bare metal area.Smooth mixing and application will help to eliminate or reduce any pinholes.


Best Practices - Body Preparation - Step 4


Block or Sand the Body Filler

Begin sanding with an 80 grit file, block or DA, and then apply the guide coat to identify any pinholes or low spots.Wipe off any excess debris then blow with clean, dry air to remove sanding dust and inspect again for pinholes and low spots.The objective is to level the filler surface and improve surface finish.

Best Practices - Body Preparation - Step 5


Feather Edge and Apply Putty or Glaze

Feather edge the filler and surrounding paint with a DA using 180 grit sandpaper.  Sand the area from high toward low areas / from center toward outer edge then blow with clean, dry air. Apply a skim coat of Putty or Glaze over the repair area, overlapping the paint feather edge. Final sand with 180 to 220 grit, as per paint manufacturer’s recommendation, then blow with clean, dry air.  Examine for coarse sand scratches, pinholes or low spots. The objective is to improve the finish and eliminate solvent penetration under the edge of the repair area.

Best Practices - Body Preparation - Step 6


After this process has been complete, any other damages can be assessed and worked on before the vehicle gets a fresh coat of paint. Once the paint job has been completed, please follow our Best Practice for Defect Removal and Buffing.



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