Carmex S0250C4224UN Thread Mill Internal 3 Flute Unc

Product Description

The CARMEX S0250C4224UN is a solid carbide helical flute thread mill designed for cutting internal UNC threads in precision machining applications. Built to mini thread mill specifications, it features 3 flutes with a TiAlN coating for extended tool life in abrasive materials. The shank diameter is 0.250 inches with a cutting diameter of 0.138 inches, making it well suited for small-diameter internal threading work. The overall length is 2.5 inches with a length of cut of 0.420 inches. This tool is intended for use by machinists and CNC operators working on tight-tolerance threaded features in ferrous and non-ferrous workpieces.

This thread mill is appropriate for CNC machining centers performing internal thread milling operations where tap breakage risk is a concern or where a single tool must produce multiple thread sizes. At 24 teeth per inch, it is configured for standard UNC thread production. The mini thread mill classification makes it a practical choice for small-bore applications in production or job-shop environments. Coolant-through is not supported, so external coolant or mist lubrication should be used during operation.

Key Features

• Solid carbide construction rated to material grade MT7 for rigidity and wear resistance
• TiAlN coating reduces heat buildup and extends tool life in demanding cuts
• 3-flute helical design improves chip evacuation during internal thread milling
• 24 TPI UNC thread standard configuration
• Mini thread mill classification suited for small-diameter internal threading
• 0.138 inch cutting diameter enables work in tight-bore features

Compatibility

Designed for internal UNC thread milling operations on CNC machining centers accepting a 0.250 inch shank diameter toolholder.

Installation Notes

Installation and operation of this tool should be performed by a qualified machinist or CNC programmer familiar with thread milling toolpaths. Ensure the toolholder collet or chuck is properly torqued and that runout is minimized before cutting. Power down or e-stop the machine and confirm the spindle is fully stopped before changing tooling. Do not use this tool for tapping operations - it is designed exclusively for helical interpolation thread milling cycles.