Metal Working Tools

Metal working tools are often overlooked when discussing body shop operations. Quite often articles on the subject center around such topics as painting and paint equipment, welding techniques and finishing procedures. But tools are the backbone of everything that you do to repair damaged vehicles, regardless of the extent of that damage. When the discussion turns to tools, it covers everything from screwdrivers and scrapers to dolly and pick hammers to wrenches and chisels.

BASIC TOOLS

Basic tools are those that every technician should have in their toolbox. This would include wrenches, sockets, standard screwdrivers and pliers. These are the tools needed to remove damaged components from a vehicle, such as doors, hoods and fascias. Then there is a whole group of special screwdrivers (e.g. Torx) and pliers (e.g. snap ring), plus locking pliers. And a basic tool set would also have putty knives, scrapers, utility knives and similar items.

Common power tools used in a body shop are included in the basic tool kit. Among those items would be sanders and grinders (electric or pneumatic), air saws and chisels. Also, polishing and buffing equipment are in this group.

Basic tools are used for a wide range of tasks in the body shop. But, when it comes time to fix sheet metal, special tools are needed that are only found in the tool box of the body shop professional. And using these tools requires skill that is honed after years of practicing this trade.

BODY HAMMERS

The first group of metal working tools is the hammer. While everyone is familiar with ball-peen, claw and sledge hammers, there are special hammers that are used for specific metal shaping operations (Figure 1). Large, flat-head hammers are used to flatten sheet metal. A hammer with a rounded head forces a curve into the sheet metal. One that is flat and smooth is used to work damage out of the sheet metal. Finally, a serrated body hammer head will shrink sheet metal that has been stretched due to collision damage. Let’s take a closer look at each 
type of hammer.

A picking hammer has a pointed tip on one end and a flat head on the other. The main purpose of the picking hammer is to remove small dents. The pointed head raises low spots from the inside. A gentle tap in the center of the low spot will usually raise the sheet metal to remove it. Picking hammers are available with a variety of pick lengths (longer picks can reach behind body panels) and pick points (from pencil sharp to smooth point).

Pick hammers should be used with care. If swung with excess force, the point can puncture the sheet metal, causing a much bigger problem than the original one. Remember, the thickness of sheet metal has decreased with the increased use of HSLA (high strength/low alloy) steel. A pick hammer should be used on small dents with minimal force. Large dents require a different type of hammer. The bumping hammer, with its large, smooth face, can direct force over a large area to straighten a dented panel. This hammer is not a finishing hammer as it is used to work areas that require a large force, not a finished appearance.

Concaved surfaces can be repaired using a bumping hammer with a crowned surface. The curved face allows such surfaces to be bumped without the danger of stretching the metal. Don’t forget that the contour of the hammer must be smaller than the contour of the panel.

Finishing hammers do just that; namely, finish the surface of the sheet metal after the dent has been removed. The face on a finishing hammer is smaller than that on a heavier bumping hammer. The surface of the face is crowned to concentrate the force directly on the high spot. A second type of finishing hammer is the shrinking hammer. This type of hammer has a serrated face.

DOLLIES

Quite often, body hammers are used with a dolly that is placed behind the damaged area. A dolly is basically a small anvil (Figure 2). It acts as a surface to hold the damaged panel from the rear. While holding the dolly with one hand, the other hand is used to swing the body hammer to straighten the damaged sheet metal.

Dollies come in a variety of shapes and sizes. Each dolly is designed for a specific type of dent and a particular body contour. It is essential that the contour of the dolly selected match the contour of the body panel being repaired. Additional damage can occur if the dolly is mismatched with the body panel (e.g., a flat dolly used on a panel with a high contour).

In many cases, a general purpose dolly (one with many contours) can be used. A rail-type dolly also has many contours. For bumping in tight areas, a toe and heel dolly is used. And to straighten flanges, use the flat, right angle of the toe and heel dolly.

SPOONS

The spoon is another metal working tool that is used like a hammer or dolly. It is characterized by a long, smooth contoured surface with a handle. The flat surface distributes the striking force of the hammer over a wide area. An inside spoon can be used to raise low spots, while creases and ridges are easily removed using a spoon on the outside of a panel.

For example, place a spoon over the length of the ridge that extends over a section of a body panel. Then, strike the spoon with a hammer to flatten the ridge. This is more effective than striking the ridge with a hammer because it eliminates the possibility of denting the panel.

PICKS, DENT PULLERS AND SUCTION CUPS

This group of metal working tools use a pulling force to remove dents and other damage to sheet metal. Also, some of these tools are used in hard-to-reach places. For example, a pick can reach into a confined space. Applying the lever principle, the pick can pry out small dents. Picks are often used when doing paintless dent removal.

Creases and dents in sealed body panels that cannot be accessed from behind can be removed using a dent puller. In years past, a small hole would be drilled into the dent and a screw threaded into the hole. The hook on the end of the dent puller would grab the screw in order to pull out the dent. Nowadays, it is common practice to weld a pull pin or bracket onto the surface. This minimizes the repair work at the site of the pull pin. A drilled hole must be filled and sanded. A stud welder with pull pins and bracket is shown in Figure 3. Note: Corrosion protection must be restored on the inside of the panel as the heat from the attachment process burns off the protective coatings. Two applications of inner panel corrosion protection such as Mopar Part No. 68042970AA or 3M Rust Fighter I, with a 30-minute flash period between coats should be sufficient.

The operation of the dent puller is simple. The screw, pin, or bracket is grabbed by the hook on the end of the puller. A large slide weight is pulled back against the handle to provide the force that pulls the object attached to the sheet metal. This force pulls out the dent. It’s a simple tool that has been around a long time. Note: Dent pullers requiring a hole are typically no longer recommended due to the advent of stud welders. Any holes created must be welded shut and corrosion protection must be applied to the heat affected area(s).

Finally, the suction cup can pull out a shallow dent that has not creased the sheet metal. It’s a simple tool to use. Lock the suction cup in the center of the dent and pull. In many cases, the dent is removed without any damage to the paint. That’s a real bonus when no refinishing is required.