Hertel K007041AS Spiral Point Sti Tap 10-32 Unf 2 Flute

Product Description

The HERTEL K007041AS is a spiral point STI tap designed for cutting 10-32 UNF threads in prepared or damaged holes that require a Helicoil-style thread insert. Built from high-speed steel with a bright, uncoated finish, this plug-chamfer tap is suited for through-hole threading operations in production and repair environments. The 2-flute spiral point geometry pushes chips forward ahead of the cutting edge, reducing chip packing in through-hole applications. With an overall length of 2.5 inches and an H3 thread limit, it holds tight tolerances appropriate for STI thread inserts. Machinists, toolroom technicians, and maintenance mechanics are the primary users of this tool.

This tap is used in applications where a standard 10-32 UNF thread has been stripped or damaged and requires restoration using a Helicoil or compatible thread insert. The STI thread form is intentionally oversized relative to the standard UNF profile, allowing the insert to bring the finished hole back to the nominal 10-32 specification. Common use cases include aerospace component repair, automotive thread restoration, and general machining shops working with aluminum, mild steel, and similar machinable materials. The plug chamfer — typically 3 to 5 threads — makes it appropriate for through-hole or sufficiently deep blind-hole applications.

Key Features

• STI UNF thread form: prepares holes for Helicoil-style thread inserts to restore 10-32 UNF threads
• Spiral point geometry pushes chips forward, reducing packing in through-hole operations
• H3 thread limit for controlled tolerance fits required by STI insert specifications
• High-speed steel construction provides durability across a broad range of workpiece materials
• Bright uncoated finish suits general-purpose use without added coating cost
• Helicoil Reference Number 3FSA for direct cross-reference in insert installation kits

Compatibility

Designed for use in applications requiring STI UNF thread preparation for Helicoil-style thread insert systems; Helicoil Reference Number 3FSA. Fits standard tap handles and machine tap holders accepting the shank dimensions of this tool.

Installation Notes

This tap is installed by machinists or maintenance technicians using a tap handle, tapping arm, or CNC machine tool with appropriate speed and feed for the workpiece material. The workpiece should be secured and the hole drilled to the correct STI tap drill diameter before threading. Use cutting fluid appropriate for the workpiece material to extend tap life and improve thread quality. Do not force the tap if resistance increases unexpectedly — back off and clear chips before continuing.