It is possible to both line and shade with a single tattoo gun, but it requires taking apart the gun and changing its settings between the lining and shading steps. It is highly recommended that two tattoo guns be used, each adjusted to the correct speed and needle depth for proper tattooing before beginning to ink a tattoo.
Depress the armature bar--the thick metal bar above the electric coils--and examine the gap between the front spring of the armature bar and the contact screw. Set the gap for line work by turning the contact screw until the gap between the tip of the screw and the front spring of the armature bar is the approximate thickness of a U.S. dime (a little bit more than 1mm).
Attach an appropriate needle tube to the tattoo gun. Insert the needle bar into the tube and fit the end ring of the needle bar over the rubber grommet on the armature bar. Loop a rubber band around the tattoo gun, encircling the back of the frame and the front of the needle bar, to cut down on vibration and lateral movement of the needle bar.
Examine the needle with a jeweller's loupe or magnifier while depressing the armature bar. Adjust the needle tube so that the length of needle that protrudes from the tip matches the gap of the contact screw.
Set the speed of the tattoo machine for line work. Some machines display a readout of voltage. Six volts is appropriate for lining. Most tattoo artists adjust voltage by listening carefully to the sound of the gun--it should produce a steady buzz or a hum. The sound shouldn't crackle or sound make a staccato noise such as those made by machine guns or typewriters.
Check the needle while the tattoo gun is activated. The rapidly moving needle should look like one solid column. If it looks like a multiple columns or you see a ghost image, tighten the rubber band on the needle bar to reduce or eliminate the lateral movement.
Set the gap between the armature bar and the contact screw for shading to approximately 2mm, or the thickness of a U.S. nickel.
Attach a needle tube appropriate for shading to the tattoo gun. Insert the matching needle bar into the tube and secure it. Examine the needle tip with a magnifier; and adjust the needle tube and rubber band properly, as you did for the lining gun.
Reset the speed of the tattoo machine for shading. Shading requires a slighty slower speed than line work. Adjust the speed by eye and ear. The hum or buzz should be a deeper sound than that made by a machine set for lining.
Put on a pair of latex or nitrile gloves prior to handling any sterile equipment. Tattoo needles, needle bars, tubes, and grips should all be surgically sterile before beginning. Tattoo and piercing materials can be sterilised in an autoclave or purchased sealed in sterile packets.
Never under any circumstances use tattoo equipment, needles, or inks that you are not 100 per cent certain are surgically sterile or free of contaminants. In almost all cases, tattoos are permanent. Take the care and time to learn the right methods or you may make a mistake that lasts a lifetime. Many serious diseases can be transmitted through blood or by unsanitary tattoo and piercing equipment. Before beginning any body modification, an artist must have a working knowledge of how to prevent the spread of blood-borne pathogens.