The basic machine was invented by Edison and patented in the United States in 1876 U.S. Patent 196,747, Stencil-Pens. It’s original intention was as an engraving machine, but was modified by Samuel O’Reilly who later patented a tube and needle ink reservoir.
The tattoo machine is essentially an electromagnet powered by a power supply. An artist will dip the needles into a small disposable cap filled with ink. The needles are soldered to a bar which is attached to the electromagnet.
When power is applied to the magnet-bar combo, the needles vibrate together up and down thousands of times per minute. As the needles make holes in the skin, the ink is injected under the skin, between the permanent bottom layer and the surface layer.
The tattooing technique of putting the ink at the right depth is very important. If the needles penetrate too deeply, the ink will get mixed with body fluid and may cause the color to spread. If it is not placed deep enough, the tattoo will fade and come out prematurely as skin is shed and renewed.
Most modern tattoo machines have allowed more control of the needle depth, speed, and force which has allowed more precision. The newer machines have even opened up a whole other flavor of tattooing, permanent make up.
Each artist will tune their tattoo machines in a way most appropriate for the way they tattoo. Stroke length, and speed at which the tattoo machine runs can vary greatly from one artist to another based on many factors including an artist’s hand speed and personal style of tattooing.
Proper force needs to be present to ensure the needles can penetrate into the upper layers of skin. The size of the needle configuration influences the amount of force needed to penetrate the skin layers.
The basic design of the tattoo machine has not changed drastically from its original design. Improvements have been made and variations have evolved. It was only in 2000 that a tattoo artist, Carson Hill, started Neuma. Neuma manufactures a different type of tattoo machine. From what I’m seeing in the forums, its popularity is growing.
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