Taps and dies

Taps and dies are cutting tools used to create screw threads in solid substances including, but not limited to, metal, wood, and plastic. A tap is used to cut the female portion of the mating pair (e.g. a nut). A die is used to cut the male portion of the mating pair (e.g. a bolt). Other than pipes, it is more common to create the hole into which a bolt is screwed than to create the item that is screwed into a hole. Thus, taps are often more commonly available. The process of cutting the threads in a hole is called "tapping" the hole.
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