A tap and die chart corresponds to various drill sizes and diameters, and to read it, simply match the size of the drill with the appropriate characteristics, such as the thread count per inch and the material type of the drill. Taps are specialty devices used to cut internal threads for various machining applications.
Taps typically come in four styles. These include taper taps, which are used to cut threads that go through the hole and plug taps, which are tap threads that only partially go through the hole. Bottoming taps are also used when it is necessary for threads to go entirely to the hole's bottom, and machine screw taps are one of the finest and smallest taps available, designed for small-diameter holes. You find out the size of the hole to drill by checking a tap drill sizing chart after accounting for the thread and diameter.
Dies are designed for cutting external threads, and the correct size of the die is determining according to a similar chart. To create the hole, a properly sized die is inserted and turned into the handle. It is important for the die to stay lubricated and for users to back up as soon as the slightest chipping or damage occurs.