Scientific Cutting Tools TM187-32 Thread Mill 1/4-32

Product Description

The SCIENTIFIC CUTTING TOOLS TM187-32 is a straight flute thread mill designed for cutting internal 1/4-32 UNEF threads in a single helical pass. Built from submicron-grade solid carbide, it delivers consistent thread geometry and extended tool life in ferrous and non-ferrous materials. The tool features a 0.187-inch cutting diameter, a 0.545-inch length of cut, and a bright (uncoated) finish suited for applications where coating adhesion or dimensional interference is a concern. With three straight flutes and 32 teeth per inch, it produces clean, accurate threads in compact bores. A 1/4-inch shank makes it compatible with standard end mill holders and collet chucks. Machinists and toolroom technicians install this tool in CNC machining centers using thread-milling cycles.

This thread mill is suited for internal UNEF threading operations in precision machining environments, including job shops, aerospace component production, and general metalworking. It handles minimum nominal bore diameters of 1/4 inch and is particularly effective in blind-hole applications where tap breakage risk is a concern. At 2.5 inches overall length, it offers sufficient reach for most standard workpiece depths while maintaining rigidity in the cut.

Key Features

• Submicron-grade solid carbide construction for wear resistance and dimensional stability
• Straight flute design with 3 flutes and 32 TPI for 1/4-32 UNEF internal threads
• 0.187-inch cutting diameter with 0.545-inch length of cut
• Bright finish - no coating - minimizes dimensional buildup on cutting edges
• 1/4-inch shank diameter fits standard collet chucks and end mill holders
• No coolant-through requirement; compatible with flood or mist coolant externally

Compatibility

Designed for use in CNC machining centers capable of executing helical thread-milling cycles; compatible with standard 1/4-inch collet chucks and end mill holders for internal UNEF 1/4-32 threading applications.

Installation Notes

Thread mills must be run using a CNC thread-milling cycle (helical interpolation) - do not use in manual or rigid tapping mode. Ensure the spindle and tool holder are clean and within runout tolerance before installation, as excess runout directly affects thread accuracy. Power down the machine and follow lockout/tagout procedures when changing tooling. Program climb milling direction for internal threads unless the machine or material requires otherwise.