A tattoo machine (don’t call it a gun) is basically a metal frame with two electromagnets that convert DC power to AC through a simple mechanical oscillation. Tattooists use them everyday, and they are a vital tool for all tattoo studios. Therefore, they have to be reliable, sufficiently strong, and well-tuned. In use, the machine is connected to a (sterilized) tube with a long needle running through it. The needle has a little loop on the end which connects to a little nipple at the tip of the armature bar. Power is connected to the circuit, and when the artist steps on the pedal, the electromagnets yank the armature bar downward, driving the needle into your skin, and releasing the top spring from the contact screw, which breaks the circuit mid-stroke. The spring then bounces back, closing the circuit once more, and the whole cycle starts again. This happens anywhere from 80 to 150 times per second, depending on how an artist is using that particular machine.
