Just a week after Ørsted published his findings that following September, the brilliant André-Marie Ampère was able to develop new mathematical descriptions explaining the relationship between electric current and magnetic fields. And yes, we get the word "amps" in honor of Ampère. These mathematical descriptions were expounded further by the great scientists Faraday, Maxwell, and Hertz.
Enter William Sturgeon, one of the early inventors of the electromagnet. In 1825, Sturgeon realized he could magnify the power of the electric field by winding wire around an iron core (example of Sturgeon's electromagnet shown at right). Sturgeon demonstrated his electromagnet by lifting a nine pound weight with only a 7 ounce magnet.
Sturgeon's electromagnet was a brilliant idea but it was limited in power because of the lack of wire insulation. Sturgeon was only able to build single-wrap electromagnets since the copper wire with which he worked was uninsulated. The American scientist Joseph Henry designed a far more powerful electromagnet by insulating the copper wires with silk, enabling many wraps of the wire in 1827. One of Joseph Henry's electromagnets was able to lift an incredible 2,063 pounds!
Modern tattoo machines use electromagnets very similar to the magnets that Sturgeon and Henry designed more than 180 years ago.
Many more scientists paved the way to the invention of the electric motor, but it was Sturgeon who was able to demonstrate one of the first practical DC motors in 1832. Countless inventions followed and the electromagnetic revolution was fully underway.
Thomas Alva Edison, that great American inventor, understood electricity and invention better than almost anyone. In 1876, Edison received a patent for the "electric pen" used as a duplicating tool (US Patent 180,857). The complete device required the use of wet cell batteries, various wires, a cast-iron duplicating press with an ink roller, and the electric motor-driven "pen" (shown at left). The pen was used to perforate paper to create a stencil for copying documents. It operated with an electric motor to drive a rotary wheel. The pen was not particularly commercially successful for Edison but did well enough for A.B.Dick, who purchased a license for the technology from Edison.
It was Samuel F. O'Reilly of New York who then realized that the electric pen could be
adapted for use as a tattoo machine. O'Reilly modified the Edison electric pen to make it more suitable for tattooing. It was for this insight that
Samuel O'Reilly is widely credited as having invented the first electric
tattoo machine. O'Reilly's patented his tattoo machine in 1891 (
US Patent 464801).
Edison actually created two versions of the electric pen. The first version was the aforementioned 1876 design that was the forerunner to Samuel O'Reilly's rotary style tattoo machine. The second version (shown at left) was patented in 1877 and employed alternating electromagnets (
US Patent 196,747).
Tom Riley of London filed for a patent for a single electromagnetic coil tattoo machine in 1891. This was a scant 20 days after Samuel O'Reilly filed a patent for a rotary-style tattoo machine built on Thomas Edison's engraving pen (reference needed). However, with the exception of the resurgence of rotary styled tattoo machines, Tom Riley's tattoo machine is said to be the closest forerunner to modern electromagnetically controlled tattoo machines.
Alfred Charles South, also of London, improved upon Tom Riley's design and produced the first two-coil electromagnetic tattoo machine.
Charles Wagner improved upon tattoo machine design in 1904 (
US Patent 768,413). Wagner's device consisted of a pair of electromagnets oriented perpendicularly with respect to the artist's hand position.
Wagner's device begins to closely resemble modern devices in that it allowed for easy interchangeability of the needle bar and needle carrier. This allowed the tattoo artist to easily change needles depending on whether a liner or a shader needle was required. The tip of the device consisted of an ink chamber into which ink could be externally added and included a plate spring to regulate ink flow and to steady the needle.
Wagner's device also allowed for adjustment of the spring tension of the armature by means of a screw to adjust the force of the needle strike, essentially inventing what is now referred to as the "contact screw" in modern machines.
Percy Waters made the next leap towards modern designs with a tattoo machine patent in 1929 (
US Patent 1724812). For the first time, we see the L-style frame and the twin electromagnets oriented parallel to the artist's hand.
The Waters machine also dispensed with the compression spring of Wagner's machine in favor of a "leaf spring" (14) for adding tension to the armature but is still adjustable via a contact screw (21). The device was actuated by a finger switch located at the front of the machine (27) and continued the practice of an ink reservoir within the hand-piece.
Eventually, modern tattoo machines abandoned the use of ink reservoirs
but more or less follow the Percy Waters design. However, additional
patents continued to emerge.
During the 1950's there were additional patents issued for surgical devices used to mark patients with pigment (
US Patent 2588623 and
US Patent 2840076). These devices were departures from the electromagnet-driven devices and more closely resemble cosmetic makeup tattoo devices than body art tattoo devices so they are not discussed further in this article.
Carol Nightingale filed a patent in 1978 (
US Patent 4159659). This device added complexity to the machine with the goal to allow for better precision, with changes to the armature bar, the ability to adjust the electromagnet coil positioning, screws to adjust the positioning of the leaf spring, and further modifications to the needle guide.
Patents have continued to be filed over the past 30 years since Nightingale's design. Additional patents relate to attempts to introduce various motors, to integrate a battery (Keith Underwood;
US Patent 6,550,356), to control unnecessary vibration, to sound-proof tattoo machines, and so on. A comprehensive review of the continued innovations of tattoo machines into the present time is another topic altogether....
The nineteenth century produced some tremendous advances in science and technology. One of the great minds of the time was the Danish scientist Hans Christian Ørsted