Harvey Tool 71020-C3 Helical Flute Thread Mill 6-32 6-40

Product Description

The HARVEY TOOL 71020-C3 is a solid carbide helical flute thread mill designed for cutting both internal and external UN threads in the 6-32 and 6-40 thread series. With a 0.0980-inch cutting diameter, a 3/16-inch (0.1875-inch) shank diameter, and a 2-inch overall length, this tool is built for precise thread milling in tight bores and close-tolerance applications. The AlTiN coating provides elevated heat resistance and extended tool life in ferrous and hardened materials. Four helical flutes deliver smooth chip evacuation and consistent thread form on each pass. Machinists and tool-and-die professionals rely on this style of thread mill for flexibility across multiple thread pitches with a single tool.

This thread mill is suited for CNC machining centers performing thread milling operations on both internal and external UN-standard threads in the 6-32 and 6-40 pitch range. It is appropriate for use in production machining, mold and die work, and precision component manufacturing where conventional tapping poses breakage risk in hard or brittle materials. The compact cutting diameter of 0.0980 inches makes it well suited for small-diameter threaded features typical in instrument, aerospace, and precision mechanical assemblies.

Key Features

• Cuts both 6-32 and 6-40 UN internal and external threads with a single tool
• 0.0980-inch cutting diameter for small-bore and fine-feature thread milling
• AlTiN coating for improved heat resistance and longer tool life in ferrous materials
• 4 helical flutes for smooth chip flow and consistent thread form
• Solid carbide construction for rigidity and dimensional stability
• 0.0500-inch neck diameter allows access to shallow internal thread features

Compatibility

Designed for CNC machining centers capable of helical interpolation; compatible with UN-standard thread forms in the 6-32 and 6-40 pitch range for both internal and external threading applications.

Installation Notes

Installation and operation should be performed by qualified machinists on CNC equipment capable of helical interpolation. Secure the shank in a collet or end mill holder appropriate for a 3/16-inch shank before running. Verify spindle speed, feed rate, and depth-of-cut parameters against the thread mill manufacturer recommendations for the workpiece material before engaging the cut. Do not use in manual milling machines or non-interpolating setups.