Thread cutting tap - has reduced dia. shank portion to permit retrieval of tap on fracture

摘要

The thread cutting tap has a shank with a portion, having a reduced cross-sectional area which is 15 to 20% less than that at the likely point of fracture of the cutting area. In the event of fracture, this occurs outside the workpiece which permits easy retrieval of the broken tap and prevents the need for scrapping the work.