There many different sizes of needles, and there are two types. There is a difference between whats called a liner and a shader. The shader is much bigger and it shouldn't "spew ink everywhere", but obviously it puts out much more ink than a liner because its designed to shade/color and not just lay a line. A tap tattoo is how they do tattoos in polynesian and japanese cultures traditionally. They have a needle and a guide, and they use a little mallet type thing to tap the back of the needle through the guide into your skin. It takes a long time, but its supposedly less traumatic to your skin. I've never gotten one, or seen one done though.
