A tattoo machine (never call it a "tattoo gun") is a hand-held device for creating a tattoo, i.e. marking skin with ink. Tattoo machines
utilize electromagnetic coils in alternation to move the needle bar up and down, which drives the pigment into the skin.
The basic machine was invented by Thomas Edison, and patented in the United States in 1876, as the "Autographic printer", which was intended
as an engraving device. In 1891, Samuel O'Reilly found Edison's machine could be modified to introduce ink into skin, and patented a tube and
needle system to provide an ink reservoir.
In fact, modern tattoo machines are very different from the machine O'Reilly invented. O'Reilly's machine was based on the rotary technology
of Edison engraving device, the first practical application of an electric motor. Modern tattoo machines use electromagnets, the first use
of which was a single coil machine patented by Thomas Riley of London, England Dec 28, 1891 twenty days after Sam O'Reilly filed his U.S.
patent for his rotary machine. Thomas Riley's machine had a single coil and was a modified door bell assembly contained in a brass box.
The modern configuration of two coils was patented by Alfred Charles South of Cockspur St. London (Patented London Jun. 30th 1899)It was
heavy and was often used with a spring attached to the top of the machine and to the ceiling to take most of the weight off the operators' hand.
Most tattoo machines can control needle depth to almost any degree and thanks to this control, tattooing has become a very precise art form.
It is, in fact, so precise that a kind of facial tattooing has attained mainstream popularity in the United States of America. The procedure
is called dermapigmentation or "permanent cosmetics".
Traditional 2 coil tattoo machine 4 views
How it works
Basically the machine works similar to alternating current— charge causes magnets to pull downward on the bar, which disconnects the circuit
and allows the upward force of the spring to pull the bar upward.
1. Power is conducted by wires in two different directions: Through the coils to the adjustable contact screw (E), and through the frame
(A) to the contact spring, (above C), via the armature spring (D).
2. Current, flowing between the contact screw and the contact spring, completes the circuit, causing:
3. The electromagnetic coils (B) to pull down on the armature bar (C), which causes:
4. The needle bar (F) to move down with it, the needles at the end of the needle bar penetrate the skin.
5. With the circuit at (2) broken, the armature spring (D) is free to exert its upward force again, causing the circuit to close with the
contact made, again, at (2).
This process repeats between 80 and 150 times a second, providing the artist with a means to penetrate the skin with ink without moving his hand.
The frame (A) can be of a conductive material such as iron, brass or copper and plastic bushings at the contact points are to be used to
isolate the current from the frame. The capacitor (pink) regulates current flow. The needle tube (G) provides a grip for the artist's control,
and a small reservoir at the tip for ink.
The needle(s) (small; not shown), are soldered to the needle bar (F). Finished needle bars are made by soldering small needles to the bars
in varied numbers, depending on the desired coverage. For thicker lines and for shading in large areas, an appropriate sized "shader"
needlegroup is used. The tube's size, at the mouth, must be appropriate to accommodate the width of the needle bar.