Wrapped coils, made from insulated copper wire and iron, are the electromagnetic backbone of any tattoo gun. The coils come in three different sizes, 8, 10 and 12, which refers to the number of layers of wire wrapped around core of the coil. More layers means a more powerful gun, since the coil conducts electricity. For example, an 8-wrap coil powers a tattoo machine that uses smaller needles, while a 12-wrap coil powers a tattoo gun with larger needles. You can wrap your own coils at home or by using a coil-winding machine, and the coils are purchasable online.
Hold the plastic bobbin by the widest end with one hand.
Wrap the insulated copper wire two or three times around the wide end with your other hand, leaving about 10 cm (4 inches) of wire sticking out.
Wrap the wire around the bobbin, being careful to keep the coils tight and close together. You should not be able to see any part of the bobbin's body after you wrap the wire.
Pull the wire back to the other side of the bobbin, and begin winding it again. Each layer of wire should start at the same end. You must wind the wire at least eight times to create the minimum strength wrap coil. If you have a coil-winding machine, you can substitute mechanical coil winding for the first four steps.
Leave another 10 cm (4 inches) of wire sticking out of the bobbin, and wrap the coils with one layer of electrical tape. This will prevent the coils from electrocuting you and hold the wrapping in place. There should now be two 10 cm (4-inch) wires coming out of the starting end of the coil.
Cut a 2.5 (1-inch) shrink-wrap sleeve to fit around the coil. Heat the shrink-wrap so it is tightly around the coil.
Repeat steps 1 through 6 to create a second wrap coil.
With the two wrap coils next to each other, twist the two starting wires together. These are the wires you left sticking out when you began wrapping the coils.
Push the remaining two wires to the back of the coils. With the coils laying on a table, the front wires will be on top and the back wires should be on the bottom.
Use a wire cutter to cut the wires to the correct length. You must measure this length depending on the tattoo gun you use.
Use a soldering gun to burn the insulation away from the ends of the two back wires. You should remove about 2 cm (3/4 inch) of insulation.
Place rubber insulation around the two back wires, leaving 1.25 cm (1/2 inch) of wire poking out.
Bend the wires towards you, and align them with the solder lugs. This step may require a wrench or holding device so you can safely solder the wires to the lugs and capacitor.
Place the capacitor so that each end can be firmly soldered to the wires and soldering lugs.
Solder the wires, lugs and capacitor using a soldering gun. At the same time, solder the front twisted wires together so they will not come apart.
Use a 0.6 cm (1/4-inch) shrink-wrap sleeve to shrink wrap the base of the soldering lugs. This will ensure that the machine does not short out.
A vice may help you hold everything in place while soldering.
When soldering, be careful to follow all necessary safety procedures, as the soldering gun and iron become very hot and could burn you. Test the wrap coils in your tattoo gun before using it on a person.