How do you use a tattoo gun?

Power is fed from a supply unit to a handheld electromagnet tattoo machine. The cycle of power is fed into the magnets in opposite polarity thereby making a flexed armature bar move upwards and downwards at a fast rate of speed to which a needle is fixed upon. The speed of the needle's movement is regulated by the power supply, and the depth of same is determined by the placement of the tube. The overall tension of the machine is regulated by gap of same from the contact screw to the front spring and the angle of the contact screw plays a major role in the proper running of the machine.