the hole and are fed down into the part, deforming the metal in a controlled, predicted way. Grease is often used to lubricate this swaging process, which is also called roller swaging. A swaging machine works by using two or four split dies which separate and close up to 2,000 times a minute. This action is achieved by mounting the dies into the machine's spindle which is rotated by a motor. The spindle is mounted inside a cage containing rollers (looks like a roller bearing). The rollers are larger than the cage so as the spindle spins the dies are pushed out to ride on the cage by centrifugal force, as the dies cross over the rollers they push the dies together because of their larger size. On a four-die machine, the number of rollers cause all dies to close at a time; if the number of rollers do not cause all pairs of dies to close at the same time then the machine is called a rotary forging machine, even though it is still a swaging process. A variation of the rotary swager is the creeping spindle swaging machine where both the spindle and cage revolve in opposite directions, this prevents the production of fins between the dies where the material being swaged grows up the gap between the dies. There are two basic types of rotary swaging machine, the standard (also known as a tagging machine), and the butt swaging machine. A butt swaging machine works by having sets of wedges that close the dies onto the workpiece by inserting them between the annular rollers and the dies, normally by the use of a foot pedal. A butt swaging machine can allow a workpiece to be inserted without the dies closing on it, for example a workpiece can be inserted and then the dies closed, drawn through until remain and the dies are then released, the finished workpiece would then, for example, be but still of its initial diameter for at each end. Uses Blacksmithing Swages are used for shaping the metal in various ways, to enhance its beauty or its fit for a desired purpose. Electronics In printed circuit board assembly individual connector pins are sometimes pressed/swaged into place using an arbor press. Some pins have a hollow end that is pressed over by the arbor's tool to form a mushroom-shaped retaining head. Typical pin diameter range