Harvey Tool 987122-C3 Thread Mill 6-32 Internal Carbide

Product Description

The HARVEY TOOL 987122-C3 is a solid carbide helical flute thread mill designed for cutting internal 6-32 threads in a variety of workpiece materials. It features a 3-flute helical geometry that produces smooth thread forms while reducing cutting forces compared to single-point alternatives. The shank diameter is 0.125 inches, the cutting diameter is 2.80 mm (0.110 inches), and the length of cut is 0.375 inches. An AlTiN coating increases surface hardness and thermal resistance, extending tool life in ferrous and hardened materials. This tool is sized and configured for use on CNC machining centers where thread milling is preferred over tapping.

This thread mill is suited for internal thread milling operations on CNC mills and machining centers in job shop, aerospace, automotive, and general precision machining environments. Its compact 0.125-inch shank and 2.80 mm cutting diameter make it appropriate for small-diameter 6-32 thread features with a minimum nominal hole diameter of 0.138 inches. The 32 TPI pitch and 0.375-inch length of cut allow the tool to produce full-form threads in through-holes and blind holes where rigid tapping is not practical or where tool breakage risk must be minimized.

Key Features

• Solid carbide construction for rigidity and dimensional stability in precision threading
• 3-flute helical geometry reduces cutting forces and improves thread surface finish
• AlTiN coating improves heat resistance and tool life in ferrous and hardened materials
• 0.125-inch shank diameter compatible with standard collet chuck toolholding systems
• 32 TPI matches 6-32 UNC internal thread specifications
• No coolant-through design — suitable for standard external coolant or air blast delivery

Compatibility

Designed for cutting internal 6-32 threads with a minimum nominal hole diameter of 0.138 inches. Intended for use in CNC machining centers with standard 0.125-inch collet or toolholder systems capable of helical interpolation.

Installation Notes

Thread milling requires a CNC control capable of helical interpolation — confirm program capability before setup. Secure the tool in a low-runout collet chuck or shrink-fit holder to maintain cutting diameter accuracy and protect the carbide substrate. Ensure the workpiece is rigidly fixtured, as vibration at small diameters accelerates edge wear. Follow the machine tool builder and tooling manufacturer feed and speed recommendations for the specific workpiece material and coating combination.