Scientific Cutting Tools SPTM138 Thread Mill 24-56 Tpi

Product Description

The SCIENTIFIC CUTTING TOOLS SPTM138 is a single profile thread mill engineered for cutting both internal and external threads across a range of #10-24 to #10-56 thread sizes, covering 24 to 56 TPI. Built from submicron-grade solid carbide with a bright/uncoated finish, this tool delivers precise thread geometry in a compact 2-inch overall length. The 3-flute design provides efficient chip evacuation and stable cutting action. With a 0.138-inch cutting diameter and a 3/16-inch shank, it is suited for small-diameter threading operations on CNC machining centers and manual mills where thread accuracy is critical.

This thread mill is intended for machinists and tool-and-die professionals running #10-series threaded features in ferrous and non-ferrous materials. It handles both internal bores and external profiles from a single tool, reducing the need for separate tap and die setups. The 0.075-inch neck diameter and 0.400-inch neck length provide reach into shallow threaded features while keeping deflection low. Typical applications include precision parts, fastener bores, and threaded inserts in production and job-shop environments.

Key Features

• Cuts internal and external threads with a single tool - 24 to 56 TPI range
• Submicron-grade solid carbide construction for wear resistance and dimensional stability
• 3-flute geometry promotes chip evacuation in small-diameter threading operations
• 0.138-inch cutting diameter suited for #10-series thread profiles
• 0.400-inch length of cut matches neck length for consistent thread depth control
• Bright/uncoated finish compatible with a wide range of cutting fluids and materials

Compatibility

Designed for use on #10-24 to #10-56 thread forms in both internal and external configurations. Fits standard 3/16-inch collets and tool holders on CNC machining centers and manual milling machines.

Installation Notes

Thread milling is performed by licensed machinists or trained CNC operators using helical interpolation cycles on a 3-axis or greater machining center. Secure the 3/16-inch shank in a precision collet or end mill holder and verify runout before cutting. Always confirm spindle speed, feed rate, and coolant settings against the tool manufacturer's application data for the specific workpiece material. Inspect the tool for chipping or wear before each production run.