Scientific Cutting Tools TMLR186-28A Thread Mill 1/4-28

Product Description

The SCIENTIFIC CUTTING TOOLS TMLR186-28A is a helical flute thread mill designed for cutting internal 1/4-28 UNF threads in a CNC machining environment. It features a solid submicron carbide construction with an AlTiN+ coating for extended tool life in ferrous and hard materials. The cutting diameter is 0.1860 inches with a 0.5000-inch length of cut, making it well suited for threading applications that require precision and consistency. Three right-hand flutes provide efficient chip evacuation. The 2.5-inch overall length and long-reach design give clearance for deep-bore threading operations.

This thread mill is used in production and job-shop CNC milling operations where internal UNF threads must be cut with high accuracy and repeatability. The long-reach geometry makes it appropriate for applications where standard-length tools cannot access the thread zone. It is commonly installed by CNC machinists and tooling specialists working in aerospace, automotive, defense, and general precision manufacturing environments where 1/4-28 internal threads are specified.

Key Features

• Cuts 1/4-28 UNF internal threads at 28 teeth per inch
• Solid submicron carbide substrate for rigidity and wear resistance
• AlTiN+ coating improves heat resistance and tool longevity in hard materials
• Three right-hand helical flutes for smooth cutting action and chip clearance
• Long-reach thread mill type provides access in deep or obstructed bores
• 0.1860-inch cutting diameter with 0.5000-inch length of cut

Compatibility

Designed as an OEM-style thread mill for CNC machining centers capable of helical interpolation and accepting a 1/4-inch shank diameter toolholder.

Installation Notes

Thread mills of this type are installed by qualified CNC machinists in standard 1/4-inch collet or end mill holders. Confirm runout on the toolholder before use, as excessive runout will degrade thread quality and accelerate wear. Program helical interpolation at the correct pitch and direction for 1/4-28 UNF internal threads. Do not use this tool in handheld or manual milling operations.