Scientific Cutting Tools TMLR139-24A Thread Mill 10-24

Product Description

The SCIENTIFIC CUTTING TOOLS TMLR139-24A is a solid carbide helical flute thread mill designed for cutting internal 10-24 UNC threads in a single helical interpolation pass. Built from submicron-grade solid carbide and finished with an AlTiN+ coating, it delivers extended tool life in ferrous and hardened materials. The cutter features a 0.139-inch cutting diameter, a 0.4-inch length of cut, and a 2.5-inch overall length, making it well-suited for long-reach applications where standard-length tools cannot reach the thread zone. Three right-hand flutes provide clean chip evacuation and stable cutting action. Licensed machinists and CNC programmers select this tool for precision threading operations in production and job-shop environments.

This thread mill is applied in CNC machining centers performing internal threading on 10-24 UNC tapped features. The long-reach configuration allows access to recessed bosses, counterbored holes, and deep pockets where rigid taps or short-reach thread mills are not practical. It is appropriate for use in steel, stainless steel, cast iron, and other materials compatible with AlTiN+ coated carbide tooling. The 1/4-inch shank diameter fits standard ER collet chucks and other toolholders commonly found in vertical and horizontal machining centers.

Key Features

• Submicron solid carbide substrate for rigidity and wear resistance in demanding materials
• AlTiN+ coating extends tool life and supports higher cutting temperatures
• Long-reach design provides access to recessed or deep threaded features
• Three right-hand helical flutes promote chip evacuation and cutting stability
• Cuts internal 10-24 UNC threads at 24 teeth per inch in a single interpolation pass
• 0.139-inch cutting diameter with 0.4-inch length of cut for controlled thread engagement

Compatibility

Designed as an OEM-style thread milling solution for CNC machining centers capable of helical interpolation, using a 1/4-inch shank toolholder such as an ER16 or ER20 collet chuck.

Installation Notes

Thread milling with this tool requires a CNC machining center with helical interpolation capability and appropriate G-code programming for the thread pitch and diameter. Secure the 1/4-inch shank in a balanced, properly torqued collet chuck to minimize runout, which directly affects thread quality. Confirm spindle speed, feed rate, and coolant strategy against the material being machined before starting the first pass. This tool does not support coolant-through delivery; flood or mist coolant applied at the cut zone is recommended.