Spiral Flute taps are recommended for machine tapping for all blind hole applications, particularly in soft materials such as copper, magnesium, and aluminum which produce long stringy swarf. Recoil taps are manufactured to precise standards from either High-Speed Steel (HSS) with ground threads. They have a larger diameter but the same pitch as a standard tap in order to accommodate the wire insert. The Recoil thread insert, when installed into a correctly tapped hole, will provide the applicable internal thread tolerance for the installed bolt.
Recoil STI Tap, Style: Spiral Flute, Unit of Measure: Inch, #4-40 Thread Size, UNC Thread Type, 3B Thread Class, 0.687 Inch Thread Length, High-Speed Steel, 2.000 Inch Overall Length, 0.141 Inch Shank Diameter, 0.112 Inch Square Drive