Introduction

If you follow these steps, you can patch a car dent yourself in just an afternoon and save a few hundred bucks over body shop prices.

We’ve patched quite a few car scratches and dents in our day. We used to do it the same way we tape drywall, by applying five pounds of body filler and then sanding off 4-9/10 lbs. Then we went to “boot camp” at 3M and learned there’s an easier way (as in, the correct way) to do car body repair.

We asked expert Jenn Cook, a senior technical service engineer at 3M, to walk you through the same car dent repair process. Once the car dent repair is done, you just spray on a primer coat and matching paint from the dealer or an auto parts store. The repair won’t look like a professional job, but at least it won’t stand out like a sore thumb. Here’s the process.
While you’re at it, you can also refer to these DIY car maintenance tips.

Tools Required

  • Angle grinder
  • Corded drill
  • Dust mask
  • Extension cord
  • Hearing protection
  • Safety glasses
  • Sanding block

Materials Required

  • Body filler
  • Finishing glaze
  • Latex gloves
  • Sandpaper
  • Tack cloth
  • Wax remover

Project step-by-step (6)

Step 1

Prep and Clean Before Filling

Step 2

Remove the Paint

  • Start by removing the paint inside and around the dent with 24-grit paper.
  • Switch to 80-grit sandpaper and hand-sand the entire dent.
  • Use the same sandpaper to rough up and feather the paint around the edges of the dent.
  • Clean the entire area with wax remover and a clean rag.
  • Then wipe with a tack cloth.

Sanding the carFamily Handyman

Step 3

Mix the Filler

  • Spread the filler down the mixing board in an S-shaped curve.
  • Then scoop it up and fold it over.
  • Repeat until the filler has a consistent color.
    • Don’t mix body filler on a scrap piece of cardboard. Instead, use a mixing board or an old, clean cookie sheet you’re willing to toss.

Mixing the fillerFamily Handyman

Step 4

Apply a “Tight” First Coat

  • Scoop up some filler and press it hard into the rough metal.
  • Spread the filler to form a “tight” coat. That will burp air out of the scratches and wet the bare metal.

Adding the tight layerFamily Handyman

Step 5

Add More Filler

  • Wipe on a thicker “fill coat” layer of filler to completely fill the dent.

Adding the fill layerFamily Handyman

Step 6

Sand to Shape and Glaze

  • Sand the filler to match the contours of the car body using 80- and 180-grit sandpaper.
  • Then feather the edges of the filler right up to the painted edge.
  • Next, apply finishing glaze to the entire patch and then sand with 180-grit and then 320-grit sandpaper.
  • Spray the patch with primer, then paint it.
    • Use DIY car paint sealant to keep the patch looking fresh.

Sanding the patchFamily Handyman

Next, check out how to get dent out of car with plunger.