How A Nail Gun Works

Ever wonder how your nail gun works? Learn the fundamentals of nailer operation, getting a behind the scenes look at the engineering marvels that power these game changing tools.

The most common type of nail gun is pneumatic, or air-powered. Compressed air is supplied via a separate air compressor, which is powered by either electricity or gasoline. The air from the compressor is pushed through a hose into a holding area in the nail gun; this is called an air reservoir. The typical pneumatic nail gun uses a piston with a long shaft attached to it called a driver. The driver is what makes contact with the head of the nail and forces it into the work surface. The piston is located in a cylinder inside the main body of the nail gun. The air in the reservoir is held in place by a valve, which is located above the piston.

Before the trigger is pulled, the air pressure below the piston is greater than the air pressure above it, which keeps the piston at the top of the cylinder. When the trigger of the nailer is depressed, the valve opens, forcing air into the cylinder and making the pressure above the piston greater than below it. This drives the piston down and hammers the nail. When the trigger is released, the air inside the nail gun around the cylinder is vented through the small holes drilled toward the bottom half of the cylinder. This makes the pressure below the piston greater than above it, and forces the piston back up to its starting position. Simultaneously, the valve opens back up and forces the used air through an exhaust port in the top of the nailer.