Hertel K007168AS Hss Hand Sti Tap 3/4-10 Unc H3 4 Flute

Product Description

The HERTEL K007168AS is a high speed steel hand STI tap designed for cutting Screw Thread Insert (STI) threads in a 3/4-10 UNC configuration. With an H3 tolerance class, this tap produces threads sized to accept helical wire inserts, restoring or creating strong threaded connections in parent materials that require insert reinforcement. The plug chamfer geometry — typically 3 to 5 threads of lead — makes it well suited for through-hole applications where the tap can pass fully through the material. Overall length is 4-11/16 inches with a thread length of 2-7/32 inches. The bright finish indicates an uncoated tool, standard for general-purpose HSS cutting applications. Machinists and maintenance technicians use this tap in hand-tapping operations.

This tap is used wherever a Screw Thread Insert must be installed into a 3/4-10 UNC tapped hole. Common applications include repair of stripped threads in aluminum, cast iron, steel, and other machinable materials, as well as OEM production where insert-reinforced threads are specified by design. It is appropriate for both shop and field repair scenarios in manufacturing, maintenance, and heavy equipment service environments. The Helicoil reference number for this tap is 8187-12, making cross-referencing to insert system kits straightforward.

Key Features

• 3/4-10 UNC STI thread form sized for helical wire thread inserts
• H3 tolerance class for consistent fit with standard STI insert systems
• 4-flute design provides good chip clearance in hand-tapping operations
• Plug chamfer (3-5 thread lead) suited for through-hole applications
• High speed steel construction handles a wide range of machinable materials
• Bright finish uncoated surface — ready for general-purpose use without additional treatment

Compatibility

Compatible with Helicoil STI insert systems as referenced by Helicoil number 8187-12. Designed for use with standard 3/4-10 UNC helical wire thread inserts in through-hole repair and production tapping applications.

Installation Notes

This tap is intended for hand-tapping operations performed by machinists or maintenance technicians. Before tapping, secure the workpiece firmly and ensure the starter hole is drilled to the correct STI tap drill diameter for 3/4-10 UNC inserts as specified by the insert manufacturer. Apply cutting fluid appropriate for the parent material to extend tool life and improve thread finish. Never force the tap — back off periodically to break chips and prevent tap breakage.