Harvey Tool 987176-C3 Thread Mill 7/16-20 Internal Solid Carbide

Product Description

The HARVEY TOOL 987176-C3 is a solid carbide helical flute thread mill designed for cutting internal 7/16-20 UNF threads in a milling operation. With 4 flutes and an AlTiN coating, it delivers efficient material removal and extended tool life in ferrous and hardened materials. The cutting diameter measures 0.3500 inches, the length of cut is 1.3000 inches, and the 3/8-inch (0.3750-inch) shank fits standard ER or end mill holders. Thread milling produces accurate, single-point-equivalent thread profiles while reducing tool pressure compared to tapping, making it a preferred method for precision machining environments.

This thread mill is suited for CNC machining centers performing internal threading operations on ferrous alloys, stainless steel, hardened steel, and similar materials where thread quality and tool life are critical. At 20 TPI with a 7/16-inch minimum nominal diameter, it covers standard 7/16-20 UNF fastener thread applications in production and job-shop environments. The overall length of 3.5000 inches provides adequate reach for typical blind and through-hole applications encountered in aerospace, automotive, and general precision machining work.

Key Features

• Solid carbide construction for rigidity and wear resistance in demanding materials
• AlTiN coating improves heat resistance and extends tool life in ferrous and hardened workpieces
• 4-flute helical design for smooth cutting action and efficient chip evacuation
• Cuts internal 7/16-20 UNF threads at 20 TPI
• 0.3500-inch cutting diameter with 1.3000-inch length of cut for adequate thread engagement depth
• 3/8-inch shank diameter compatible with common ER collet and end mill toolholding systems

Compatibility

Designed as an OEM-style replacement and standard tooling option for CNC machining centers requiring internal 7/16-20 UNF thread milling capability with a 3/8-inch shank interface.

Installation Notes

Installation and operation should be performed by a qualified CNC machinist or toolroom professional. Secure the shank firmly in a balanced, runout-minimized toolholder before programming the helical interpolation toolpath. Verify spindle speed and feed rate parameters against the workpiece material and cutting conditions before engaging the cut. Do not use this tool for tapping operations; it is designed exclusively for CNC thread milling with helical interpolation.