Hertel K007073AS Hand Sti Tap 3/8-16 Unc H3 Bottoming

Product Description

The HERTEL K007073AS is a hand STI tap designed to cut 3/8-16 UNC threads in Screw Thread Insert (STI) applications. STI taps cut an oversized thread profile to accept helical wire thread inserts, restoring or reinforcing threaded holes in aluminum, cast iron, and other materials. This tap carries an H3 thread limit, a 4-flute geometry, and a bottoming chamfer for threading close to the bottom of a blind hole. The overall length is 3.375 inches. It is made from high-speed steel with a bright, uncoated finish. Machinists, tool-and-die technicians, and maintenance mechanics use this tap by hand or in a tapping fixture.

This tap is suited for repair work and OEM production where standard thread forms have been damaged or where added thread strength is required. The bottoming chamfer allows full thread engagement within a few turns of the hole bottom, making it the right choice for shallow blind holes. Typical applications include thread repair on engine blocks, housings, and structural components across industrial maintenance, aerospace, and general manufacturing environments.

Key Features

• STI profile cuts oversized threads to accept standard helical wire thread inserts
• Bottoming chamfer for full thread engagement near the bottom of blind holes
• H3 thread limit for consistent fit with insert installation tools
• 4-flute design provides balanced cutting action and chip clearance
• High-speed steel construction handles a wide range of workpiece materials
• Bright uncoated finish allows visual inspection and is suitable for use with cutting fluid

Compatibility

Designed for use in 3/8-16 UNC STI thread repair and insert installation applications where a helical wire thread insert is being installed to restore or reinforce a threaded bore.

Installation Notes

This tap is intended for use by machinists or qualified maintenance technicians. Secure the workpiece before tapping and use a quality cutting fluid appropriate to the workpiece material to extend tap life and improve thread finish. Apply consistent, moderate torque with a tap wrench and back off periodically to break chips. Inspect the tap for wear or damage before each use, as a chipped or worn tap can damage the workpiece thread.