All tattoo instruments contain the same basic parts: the motor and power supply, the needle and tubing. The motor drives the needle into the skin, while the tube allows the artist control over the needle. A sturdy piece of plastic or metal operates as a handle. Tape or glue holds the machine together.
Making a tattoo gun requires basic materials found around the home. Prisoners craft makeshift machines with little trouble. In the jailhouse or the townhouse, the basic elements remain the same. Portable cassette players, electric toothbrushes and hand-held fans contain appropriate, usable motors. Remove the motor, keeping the power supply connected if possible. Guitar strings (particularly the "B" string) double as needles. Cut a length of string about 5 inches long. Ballpoint pens work as tubing. Remove the ink tube and ball from the pen. Leave the tip, which is necessary for proper needle control. Cut the pen about a half-inch shorter than the guitar string. Remove the head of a toothbrush, using the remainder as the body of your works. A pencil eraser and electrical or duct tape holds the apparatus together.
Insert the guitar string through the tube. Half an inch or so should hang out the back. Between an eighth and a quarter inch sticks out the front. Heat the toothbrush with a lighter to soften (but not melt) it. Bend the toothbrush into an "L" shape. Let the toothbrush cool before continuing. Tape the tubing on top of the long side of the L-shaped toothbrush securely. Push the eraser on the motor shaft concentrically. Tape the motor assembly securely to the back of the short side of the toothbrush. Bend the wire hanging out the back down. Stick the wire into the top of the eraser. Make sure the needle is slightly off-center in the eraser. Connect the motor to the power source, and the tattoo gun is ready to go.
Test your tattoo gun on a piece of fruit before working on a person. Thick-skinned fruit such as bananas and oranges work best. Make sure the needle creates thick, clear lines on the first pass. If it does not, try adjusting the needle. Play around with the protrusion from the tubing. Change where the needle sits in the pencil eraser. Experiment with needles of different gauges. Finally, try a different motor. Tattooing is an art, not a science. Your satisfaction is the only judge.