How to use Bondo (body putty) to fix dents and rust in your car

Marshall Brain

So you are saving money by keeping an older car, but it is starting to look a little rough around the edges. It could be having problems with dents, rust and scratches, or it could need a new paint job. We already covered scratch repair in this post. Here we will look at dents and rust.

Small dents and small patches of rust are easy to fill with Bondo, also known as body putty. This is an epoxy plastic that you use to fill the dent or replace rusted metal. It is easy to apply, and once it is sanded and painted it can make a dent completely invisible.

This video shows you the steps to applying body putty to holes and dents:

The basic steps: 1) Sand the area in and around the dent 2) Clean with alcohol 3) Mix putty and catalyst 4) Apply the putty with a spreader 5) Wait for it to harden, and then sand it smooth

The following video shows how to repair a rust spot, and then how to prime and paint the area:

Fill holes or dents in car bodywork

See also this page: How to Repair a Hole in a Car with Bondo

If you have more serious rust problems (for example, you are restoring a car that is 30 years old), it requires a little more effort. You need to cut away rotten metal and replace it. You can find dozens of videos that explain the steps here:

Classic Car Restoration: Body Work

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