Recoil Taps or Helicoil Taps or STI Taps or Screw Thread Insert Tap are used with Recoil Inserts or Helicoil Inserts only. Recoil Taps are manufactured to precise standards from High Speed steel (HSS) with ground threads and are available in Taper, Intermediate and Bottoming leads. They have a large diameter but the same pitch as a standard tap in order to accommodate the Recoil Inserts. Spiral Point and Spiral Flute machine taps are also available. For all spark plug applications pilot nose taps are available. The Recoil thread inserts when installed into a correctly tapped hole will provide the applicable internal thread tolerance for the installed bolt.
Unified Thread Class
In the unified thread system, the minimum pitch diameter for a 2B hole (medium fit) or 3B hole (close fit) are the same, while the
maximum pitch diameter is greater on the 2B hole (medium fit).Recoil taps for unified threads are made to a 3B hole (close fit) tolerance.
Metric Thread Class
In the metric thread system the minimum pitch diameter for a 5H hole (medium fit) or 4H5H hole (close fit) are the same, while the
maximum pitch diameter is greater on the 5H hole (medium fit).Recoil taps for metric threads are made to 4H5H hole (close fit) tolerance.
Recoil taps or Helicoil Taps are manufactured for every thread form including UNC, UNF, BSC, BSW, BSP, BSF, BA, NPT and ISO metric thread sizes.
Recoil taps or Helicoil taps are available in Sizes M2 to M52, UNC 2-56 to UNC 1-1/2-6, UNF 3-56 to UNC 1-1/2-12, 0BA to 6BA, BSC 5/16 to BSC ½, BSF 3/16 to BSF 1-1/4-9, BSP 1/8 to BSP 1-11, BSW 1/8 to BSW 1-1/2-6, NPT 1/8 to NPT1-11, UN 1-1/8-8 to UN 3-8 and Spark Plug Sizes M10x1, M12x1.25, M14x1.25, M18x1.5.