DOI: 10.1115/1.4058434 ISSN: 0097-6822
The Development of Tap-Drill Sizes
A. C. DanekindAbstract
Charts for tap-drill sizes as a rule are made up from the opinions of operators, without basic knowledge of the factors governing the selection of the proper tap drill. Different groups of operators in the same plant will develop different charts for the same set of conditions. The author has studied various existing charts and has devised one that takes into consideration the character of material being tapped, the bearing of thread desired, the thickness of the tapped section, and other essential factors.