For custom classic truck enthusiasts, one of the most rewarding moments comes when someone asks who handled a particular construction phase of your truck and you can say, “I did.” That is particularly true when it come to something as obvious as bodywork.

If you’re rebuilding an old truck bumping out dents generally is part of the process and when that time comes a decision will have to be made, either pay someone for their time and talent or learn to do it yourself. It’s understandable that the though of attempting bodywork for the first time is downright intimidating, especially when you look at an entire truck. But a less scary approach is to look at one part at a time. Start with something simple, like a dented fender and ignore the rest, and if you’re still nervous, think of all the money you’ll save.

In most cases sheetmetal repairs are done in the reverse order of the way the damage was done. As an example, if you ran into a fence post and the damage started at the front of the fender and continued for 18-inches or so to the rear, the repair process would start at the end of the crease and move forward. If the damaged panel has some crown to it, a hammer alone can be used to bring the metal back to shape. But more than likely a hammer and dolly will be used together.

There are two techniques for using hammers and dollies—hammering on dolly and hammering off dolly. Hammering on dolly is like using a hammer on an anvil. To repair the damaged area a dolly that is similar in shape to the panel is used. Using a low crown hammer, start the hammering around the edge of the damage, overlapping the hammer blows by half the diameter of the hammer’s head as you work towards the center. As hammering on dolly means the metal is squeezed between the two, being too aggressive with the hammer blows will result in the metal becoming thinner, which means it stretches. That material has to go somewhere so it will often “grow” in the direction of the pre-existing high (or low) spot.

When hammering off dolly pressure is applied to the low spot with the dolly from the backside of a panel and the high spot is hammered from the front, this will simultaneously raise the low spot and lower the high spot with little or no stretching.

To get started in bodywork there are a few tools that should be in your garage:

Hammers

These come in a variety of sizes, shapes and weights. The heads are usually round or square and the faces will have a slight convex shape in the case of a low crown hammer, or more curvature as on a high crown hammer. In any case a flat-face hammer should never be used for body work as more often than not the edge of the face will put a “smile” shaped impression in the surface if a blow lands other than square.

In most cases a low crown hammer will be used, as it will spread its impact over a larger area than its high crown counterpart. That means there’s less of a chance the metal will be stretched. However, the shape of the panel must be considered when choosing a hammer. The curvature of the hammer’s face should be greater that the panel being repaired to prevent the edges of the hammer from contacting the metal. Along with the square or round head on one side, many hammers will have a “pick” on the other. Used to raise low spots, these picks may be pointed or chisel shaped.

Another common type of hammer face is the shrinker. These can be found with a simple crosshatch pattern or more aggressive “meat tenderizer” face. In either case the effect is to displace metal and tighten, or shrink the surface.

Dollies

There are dollies available in every conceivable shape and size and generally weight two pounds or more. Good dollies are made from forged steel, the cheaper variety are cast iron.

For versatility each dolly usually has a variety of contours so matching the shape of its surface to that of the panel being repaired shouldn’t be too difficult.

Spoons

These can be used like a dolly in situations where space is restricted. They can also be used to pry, and in some cases even used as a “slap” hammer. Like hammers and dollies, spoons come in a variety of sizes and shapes.

Grinders and Sanders

Bodywork requires the use of a variety of abrasives ranging roughly from 24-grit to around 320. Coarse abrasives are used to quickly remove old filler and paint in damaged areas and that is generally done most effectively with an air driven grinder.

For featheredging paint, preparing for the application of body filler or refinishing materials, finer grits are used on a DA, or a dual-action sander. Air driven, these sanders have two modes, circular or oscillating, or random orbit. In the oscillating mode, which is used more often, material is removed faster and with less likelihood of abrupt edges.

Getting started

Unfortunately, explaining how to do bodywork is like trying to tell someone how to ride a bike, the best way to do either is to jump on and give it a try. Equip your shop with a few basic body tools and try some minor repairs. As you gain ability and confidence, consider some of the additional tools and equipment we’re showing here. And, of course, watch the pages of Custom Classic Trucks for more tips on doing the bump and grind. CCT

SOURCE
Eastwood
800-343-9352
http://www.eastwood.com
HarborFreight
3491 Mission Oaks Blvd
Camarillo
CA  93011
800-444-3353
www.harborfreight.com
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