An air hammer is any device that uses highly pressurized air to drive a hammer into a workpiece for shaping, scoring, or plenishing (smoothing). This pneumatic device allows a craftsman to shape a piece of metal in minutes that would otherwise take hours or days, and much physical strain, to form by hand.
When someone uses an air hammer, it hits a workpiece several thousand times per second, with pressures generally around several dozen PSI (pounds per square inch). Handheld tools must be attached to tubes leading to air tanks that provide pressurized air. Some are also referred to as power hammers.
Air hammers have variable tips. Shaping and plenishing requires a hammer tip, while for scoring or cutting, a chisel tip is used. Whatever tip is used, it will be pounded thousands of times per minute into the targeted object, so human operators must take care and precaution.
For simple plenishing jobs, low pressures may be used. Soft metals like aluminum and copper are easy to shape or polish. Stronger metals, such as stainless steel, and heavy shaping jobs require setting the hammer to maximum PSI levels, consuming pressurized air more quickly.
People who are considering buying a specific model should consider the blows per minute, chisels or hammer tips included, air consumption, maximum working pressure, the size of the air inlet, the recommended hose size, weight, and the product code. It is also possible for craftsmen to build air hammers themselves, and plans can be found online.