Dollys and Body Hammers: Dent Fixing Techniques

dent on the back of a white/silver car

If you have a body hammer and a dolly, you can fix most dents yourself with a few simple techniques. This article will briefly touch on two of the most common techniques used with these tools.


Before you try to hammer any dent out with a body hammer and dolly, you need to make sure your tools are in good shape and are high quality. Using tools that are lower quality can result in rings being pressed on to the metal you are trying to fix, and causing more unsightly damage and more repair work to be done later.


These techniques should not be tried for the first time on an important project. You should instead make sure you have practiced on smaller projects, or just flat pieces of metal to ensure you have a firm grasp of how the tools work. The amount of pressure you use in your strikes can make a big difference. Make sure you understand how to translate the sensitivity in your tools.

You can go to any hardware store and purchases different sizes of flat metal to play with so you can perfect the techniques.

Hammer On Dolly

This technique is basically what it sounds like. You will place the dolly on the back side of the metal you are wanting to repair. You will use a body hammer to start to tap out the dents. With this you will be striking the metal directly on the dolly. With this method you need to remember that the metal will stretch and become softer, more pliable. Just keep hammering until the dent is gone. It can be a slow process but it’s very effective. If the metal stretches beyond what you need you will need to shrink the metal. Stretched metal is weaker and thinner. Shrinking it will restore the original strength. Shrinking requires a higher skill level. You will be working with extremely hot metals and hammers. You may also need a shrink disk and other shrinking tools to accomplish this. This is also something that should be practiced before you attempt it on a serious or important project.

Hammer Off Dolly

Again, a technique for hammering dents that sounds exactly what it is. Instead of striking the metal directly on the dolly, you strike it approximately a half inch away from it instead. This technique will push the metal in front of the hammer back, resulting in the dolly pushing the metal in the opposite direction.

To get an idea of what this does, picture a flat piece of metal. While you strike, the dolly strikes back, forming a shape similar to an S. Depending on the dent, this may be the best method to use. This method also doesn’t tend to cause the metal to stretch or weaken.

This technique tends to be more difficult than the hammer on technique, so be sure you have a grasp of how the hammer on works before attempting the hammer off technique.