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    Indianapolis, IN 46203
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8-32 Tap, Modified Bottom, UNC STI thread, H3/H4, 3 flutes, HSS-E, TiN Coated, 40° Spiral Flute

  • Item Code: 3988-4.166
  • Brand: Guhring
  • Unit Size: 1

Description

An STI tap thread tap is designed to create an oversized thread to accommodate the required Heli-Coil insert. Screw Thread Inserts (STI) are helically formed diamond shaped stainless steel or phosphorous bronze wire that screw into a threaded hole to form a mating internal thread. Screw thread inserts are a convenient way of repairing stripped out threads and are also used to provide stronger threads in softer materials than can be obtained by directly tapping the base metal.

Tech Specs

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Overall Length (mm) 60.2996
Series 3988
Coating TiN
Number of flutes 3
Shank Diameter (mm) 5.588
Square Size (decimal) 0.1311
Material HSS-E
threadtype UNC STI
Overall Length (decimal) 2.3740
Helix Angle 40°
Reach (decimal) 1.0240
Diameter 8-32
H Limit H3/H4
Brand Guhring
chamfer (decimal) Modified Bottom
Diameter (mm) 4.166