Harvey Tool 54210-C3 Thread Mill 4-40 to 4-48 Solid Carbide

Product Description

The HARVEY TOOL 54210-C3 is a single profile thread mill designed to cut both internal and external threads in the number 4 thread size range, covering 40 to 48 threads per inch (TPI). Built from solid carbide and coated with AlTiN for heat and wear resistance, this tool is suited for precision threading in hardened and abrasive materials. With a cutting diameter of 0.08 inches, a neck diameter of 0.04 inches, and a 2-flute geometry, it delivers controlled chip evacuation in tight threading applications. Machinists and CNC programmers in aerospace, medical device, and precision machining shops rely on single profile thread mills like this one for flexibility across multiple thread pitches with a single tool.

This thread mill is intended for use in CNC machining centers capable of helical interpolation. It covers the number 4-40 to number 4-48 thread range, making it useful where both coarse and fine pitch threads in the number 4 size must be produced without a tool change. The short neck length of 0.375 inches keeps the tool rigid close to the workpiece, which reduces deflection in small-diameter threading operations. Typical applications include threading small fastener holes in aluminum, stainless steel, titanium, and other materials where tap breakage is a concern.

Key Features

• Covers 40 to 48 TPI in the number 4 thread size — one tool handles both 4-40 and 4-48 in a single setup
• Cuts internal and external threads using CNC helical interpolation
• Solid carbide construction for rigidity and dimensional stability in demanding materials
• AlTiN coating improves heat resistance and extends tool life in ferrous and high-temperature alloys
• 2-flute design promotes chip clearance in small-diameter, deep-reach threading
• Reduced neck diameter of 0.04 inches allows reach into counterbored or stepped hole features

Compatibility

Designed for use in CNC machining centers with helical interpolation capability. Accepts standard 3/16-inch collet or toolholder systems. Compatible with internal and external threading operations in the number 4-40 to number 4-48 thread range.

Installation Notes

This tool must be run in a CNC machine programmed for helical interpolation — it is not a hand tap and cannot be used in a drill press or manual setup. Secure the 3/16-inch shank in a precision collet or shrink-fit holder to minimize runout, which is critical at this cutting diameter. Verify spindle speeds, feed rates, and coolant strategy against the manufacturer's published speeds and feeds for the workpiece material before cutting. Inspect the neck and cutting edge for chipping before each use, as solid carbide tools at this diameter are sensitive to improper handling.