Metal Shaping: Using a Hammer and Dolly

Metalworking Tools
photo by Matt Wright, 2014

There are lots of ways to deal with dented sheet metal on a car or truck. The protocol mostly calls for replacing the entire section, even if it means reinstalling an entire hood and painting it to match your car or truck when there's only minor damage to the car. No matter how minor the damage may be, chances are your local dealership service department or body shop is more interested in tossing the old one in the garbage and painting/installing a new one.

To body guys who have been working with automobiles for decades, the idea of tossing out a fender or door with a minor dent is ludicrous. Real body men could work the dents out of a steel panel and leave it so smooth it was ready to sand and paint. Even the more recent use of plastic body filler is a big saving over whole panel replacement. Bolting on a fender may be the easy way, but for some, there is no substitute to actually working the metal back into shape. 

Steel is an impressive material. It’s strong and flexible. You can shrink steel, or you can stretch steel. These two qualities are what make it so workable when it comes to forming or repairing a body panel on your car or truck. When your body panels were made, a flat sheet of steel was placed onto a die in a powerful hydraulic press. The press came down and stamped out the correct shape. In an instant, some of the metal in that flat panel was stretched and some of it shrank. And now you have a fender. Since we don’t have a press like that in our garage at home, we have to rely on a series of very small persuasions to get the metal to return to the shape we want. 

Metalshaping Hammers and Dollies

The tools of the trade are simple: hammers and dollies. We all know what hammers are, but these are a little more specialized in that they have different weights and differently shaped heads depending on the surface you are working. Dollies are heavy, simply shaped lumps of steel that fit into the palm of the metal worker's hand as he works.

Using the hammer and dolly method, a dent, crease or dimple can be made smooth again without the use of a welder or body filler. The metal worker finds the dent in the metal, then places the dolly on the back side of the damaged area. Using care and finesse, he then begins to tap the metal from the other side, using the hard steel dolly as a backing plate for the hammer blows.

For a higher spot, you'd simply reverse the hammer and dolly location, given you can reach the damage from the back well enough. We use the word "tap" rather than "bang" because very seldom do you have to actually smack the hammer down on the metal to get it to move. A good metal worker knows not only how hard to hit the metal with his hammer, he also knows exactly where to hit the panel and when he should hit it there.

Playing with the ways that metal stresses and relives its stresses is important to working a dent out of a panel. It's amazing to see it work, and the results are even more incredible. If you have an interest in metal working, you should buy a hammer and dolly kit and start to experiment. It takes tons of practice to even be marginally adept at it, but you'll have tons of fun!