The construction of a planishing hammer is fairly simple. The power unit (typically an air motor or some sort) is the “heart” of the machine. This can be as simple as an air chisel on some entry-level machines, or it could be a needle scaler, which will typically have more power. It could also be a riveting gun, or an air motor designed specifically for this application. Using a purpose-built air motor or a rivet gun brings a lot more controllability to the process, allowing you to “feather the throttle” a great deal, adding a valuable degree of control over the process. Air chisels and needle scalers usually have limited speed adjustment.

While somewhat unusual, some very effective planishing hammers have been built that are completely mechanical, and don’t require compressed air to operate. Check out the photo of the Mechammer in this article.

The power head is fastened to a (usually) C-shaped frame, with a receiver placed directly below it to hold the bottom die. As you’ll see, there can be a number of different lower dies used, depending on what you’re trying to accomplish with the machine. Many machines have a foot pedal that starts and stops the hammering action, although some machines use a hand-operated valve.

It’s important to be able to change the gap between the top and bottom dies. One reason is to simplify die changes, and to accommodate the use of dies with different heights. Another is to allow panels with flanges, beads, or other obstructions to be easily fed into place between the dies. The tightness of the dies (the gap between them as you’re hammering) has some effect on the way the machine works, too, and some machines are set up so the same foot pedal that starts and stops the hammering action also adjusts the gap between the dies. While not essential, this is a desirable feature.

Some machines are pedestal-mounted, so you can position them wherever you want, while other machines are bench-mounted, and a few machines can be handheld, as you’ll see.

Let’s take a look at several different styles of planishing hammers, keeping an eye out for the unique features of each type. At the end, we’ll show examples of a few machines that are often confused with planishing hammers, but are fundamentally different.

Covell Creative Metalworking
Eastwood Company
263 Shoemaker Road
PA  19464
Gitzit Tools
C. Cook Enterprises
Mittler Bros.
3491 Mission Oaks Blvd
CA  93011
TM Technologies
N. San Juan
Michigan Pneumatic