Accupro C951-25018 Thread Mill 1/4-18 Npt 4 Flute Carbide

Product Description

The ACCUPRO C951-25018 is a helical flute thread mill designed for cutting internal NPT threads in precision machining applications. Built from micrograin solid carbide and coated with TiAlN for extended tool life and heat resistance, this mill produces 1/4-18 NPT internal threads with a cutting diameter of 0.36 inches and a length of cut of 0.611 inches. The 3/8-inch shank diameter and right-hand flute direction make it compatible with standard CNC machining center tool holders. With 4 flutes and 18 teeth per inch, it delivers clean thread form on a single helical pass. This tool is installed and operated by machinists and CNC programmers working in production or job-shop environments.

This thread mill is suited for machining internal NPT pipe threads in ferrous and non-ferrous materials where solid carbide tooling is specified. Typical applications include porting, manifold work, hydraulic block machining, and pneumatic fitting threads. The TiAlN coating supports dry or semi-dry cutting conditions and is well suited for hardened steels and cast iron. The 0.25-inch minimum nominal diameter and 0.611-inch length of cut are appropriate for through and blind-hole NPT thread milling in production-volume setups.

Key Features

• Micrograin solid carbide construction for rigidity and wear resistance
• TiAlN coating extends tool life in high-temperature cutting conditions
• 4 helical flutes with right-hand cutting direction
• 18 teeth per inch for accurate 1/4-18 NPT internal thread form
• 0.36-inch cutting diameter with 0.611-inch length of cut
• 3/8-inch shank diameter with 0.0003-inch tolerance for precise tool holding

Compatibility

Designed for CNC machining centers capable of helical interpolation, using standard 3/8-inch collet or end mill holders. Suited for cutting 1/4-18 NPT internal threads per the NPT thread standard.

Installation Notes

Thread mills require a CNC control with helical interpolation capability. Verify tool holder runout before use, as excessive runout will affect thread accuracy and tool life. Coolant-through is not supported on this tool; confirm chip evacuation strategy before running blind-hole applications. Follow the tool manufacturer and machine builder guidelines for feed rate and spindle speed based on workpiece material.