Internal Thread Tools in UNC and UNF Sizes
Tap and Die sets are used to cut and restore internal and external threads precisely. A tap is used to form the female component of the assembly, as in the case of a nut or socket. A Tap is used for the internal threads. Tools like a T handle wrench are used with a tap to create or repair an internal thread.
Taper Taps have a more pronounced taper to their cutting edges. This gives taper taps a more gradual cutting action. Taper taps are most often used when the material to be tapped is difficult to work with or if the tap is of a very small diameter and prone to breakage. Features a 7-10 pitch chamfer length and starts the thread square with the workpiece.
Tap sizes should be one size larger than hole to be tapped. For example: 1/2" Hole = 9/16" Tap