Hertel K007132AS Spiral Point Sti Tap 1/2-13 Unc Hss

Product Description

The HERTEL K007132AS is a spiral point STI tap designed for cutting Screw Thread Insert (STI) threads in a range of metalworking applications. Built from high-speed steel with a bright, uncoated finish, this plug-chamfer tap is sized for 1/2-13 UNC thread form and carries an H4 thread limit for controlled fit tolerance. The spiral point geometry pushes chips forward ahead of the cutting zone, making it well suited for through-hole tapping. At 3-13/32 inches overall length with a 1-13/16 inch thread length, this tap fits standard tap wrenches and machine holders used in production and maintenance environments. Machinists, tool and die workers, and maintenance technicians are the primary users.

This tap is applied wherever a 1/2-13 UNC STI thread is required — typically in repair applications where a parent thread has been stripped or damaged and a helical coil insert will be installed to restore thread integrity. STI taps cut an oversized thread to accommodate the insert, and the finished assembly returns to standard 1/2-13 UNC thread spec. The Helicoil reference number for this tap is 8CSA. Suitable for use in steel, cast iron, aluminum, and similar materials at appropriate cutting speeds for high-speed steel tooling.

Key Features

• Spiral point geometry pushes chips forward, ideal for through-hole tapping
• STI UNC thread form sized for helical coil insert installation
• H4 thread limit for consistent, controlled oversize tolerance
• High-speed steel construction provides durability across a range of workpiece materials
• Bright, uncoated finish compatible with standard cutting fluids
• Plug chamfer (3-5 thread lead) for easy starting in through-hole applications

Compatibility

Designed for use in 1/2-13 UNC STI thread applications requiring helical coil insert installation; Helicoil reference number 8CSA. Fits standard tap wrenches and machine tap holders accepting this shank size.

Installation Notes

This tap should be installed by a qualified machinist or maintenance technician familiar with thread repair procedures. Always secure the workpiece and use the appropriate cutting fluid for the workpiece material before tapping. Ensure the correct tap drill size for the STI thread specification is used prior to tapping — using a standard UNC drill size will result in an incorrect thread form. Follow applicable shop safety practices and equipment lockout procedures when operating drilling or tapping machinery.