Harvey Tool 987144 Thread Mill 1/4-20 Internal Solid Carbide

Product Description

The HARVEY TOOL 987144 is a solid carbide helical flute thread mill designed for cutting internal 1/4-20 threads in a single helical pass. With a 0.195-inch cutting diameter and a 0.750-inch length of cut, this tool removes material efficiently while maintaining thread accuracy. The 3-flute geometry promotes chip evacuation and smooth cutting action. It accepts a 0.250-inch shank and carries a bright, uncoated finish suitable for a range of workpiece materials. Machinists and toolroom operators use this tool on CNC machining centers where a tap would present breakage risk or where thread interpolation is the preferred method.

This thread mill is suited for precision machining environments requiring internal 1/4-20 threads at 20 TPI. It performs well in production and job-shop settings where thread quality and tool life consistency matter. The helical flute design supports use in both ferrous and non-ferrous materials. Its compact cutting diameter of 0.195 inches allows entry into tight bores, and the 2.500-inch overall length provides adequate clearance for most standard machining center setups.

Key Features

• Solid carbide construction for rigidity and wear resistance
• 3-flute helical geometry promotes efficient chip evacuation during thread interpolation
• Cuts internal 1/4-20 threads at 20 TPI in a single helical pass
• Bright, uncoated finish compatible with a broad range of workpiece materials
• 0.250-inch shank diameter fits standard ER and shrink-fit collet systems
• No coolant-through requirement simplifies setup on standard machining centers

Compatibility

Designed as an OEM-style thread mill for CNC machining centers capable of helical interpolation and programmed for 1/4-20 internal thread milling applications.

Installation Notes

Thread mills require a CNC machining center with helical interpolation capability and appropriate G-code programming for thread geometry. Secure the 0.250-inch shank in a properly sized collet or toolholder before spindle engagement. Confirm spindle speed and feed rate parameters against the workpiece material before running the first pass. Handle carbide tooling carefully to avoid chipping the cutting edges during setup or storage.