Scientific Cutting Tools TM170-40A Thread Mill 1/4-40

Product Description

The SCIENTIFIC CUTTING TOOLS TM170-40A is a straight flute thread mill designed for cutting internal 1/4-40 UNS threads in a single helical pass. Built from submicron-grade solid carbide and finished with a TiAlN coating, this tool delivers the hardness and thermal resistance needed for production threading in ferrous and non-ferrous materials. It runs a 0.17-inch cutting diameter with a 0.5-inch length of cut, making it well suited for threading shallow to mid-depth bores. Licensed machinists and CNC tool-and-die technicians are the primary users. Three straight flutes provide stable chip evacuation in through and blind hole applications.

This thread mill is used in CNC machining centers capable of helical interpolation. It is appropriate for threading operations in precision manufacturing, aerospace component work, instrumentation, and general machine shop production where 1/4-40 UNS internal threads are required. The 1/4-inch shank diameter fits standard ER collet chucks and other 1/4-inch toolholders commonly used on vertical and horizontal machining centers. Overall length is 2.5 inches, keeping the tool compact for close-tolerance work.

Key Features

• Cuts 1/4-40 UNS internal threads at 40 teeth per inch via helical interpolation
• Submicron-grade solid carbide construction for rigidity and extended tool life
• TiAlN coating provides high-temperature resistance and reduced tool wear
• 3 straight flutes for consistent chip flow in blind and through-hole bores
• 0.17-inch cutting diameter with 0.5-inch length of cut for shallow to mid-depth threading
• No coolant-through design - suitable for flood or mist coolant delivery at the spindle

Compatibility

Designed for use in CNC machining centers capable of helical interpolation with a 1/4-inch collet or toolholder. Intended for cutting 1/4-40 UNS internal threads per the UNS thread standard.

Installation Notes

Install in a 1/4-inch ER collet chuck or equivalent precision toolholder, ensuring runout is minimized before threading operations begin. Program the CNC control for helical interpolation at the correct thread pitch before engaging the workpiece. Verify spindle speed and feed rate against the tool manufacturer's recommendations for the workpiece material before first use. Do not use this tool for tapping or straight-plunge operations - it is designed exclusively for helical interpolation threading cycles.