Accupro 930-00440 Thread Mill 4-40 Internal 2 Flute Solid Carbide

Product Description

The ACCUPRO 930-00440 is a solid carbide helical flute thread mill designed for cutting internal 4-40 UNC threads. It runs 2 flutes with a 0.1000 inch cutting diameter and a 0.2500 inch length of cut, making it suited for small-diameter internal thread milling in precision machining environments. The micrograin carbide substrate and TiAlN coating provide wear resistance and thermal stability at elevated cutting speeds. This tool is installed by CNC machinists and tool-and-die professionals working on tight-tolerance components where tapped holes are not practical or where thread milling is the preferred process.

This thread mill is used in production and job-shop environments for generating 4-40 UNC internal threads on machining centers. It is applicable to aluminum, steel, stainless, and hardened alloy workpieces where micrograin carbide and TiAlN coating provide the necessary edge retention. The 1/4 inch shank diameter fits standard ER collet chucks and shrink-fit holders commonly found on vertical and horizontal machining centers. It is suited for both through-hole and blind-hole applications within its length-of-cut range.

Key Features

• Solid micrograin carbide construction for rigidity and edge retention in small-diameter thread milling
• TiAlN coating improves heat resistance and extends tool life in ferrous and hardened materials
• 4-40 UNC thread form, 40 TPI, internal configuration
• 0.1000 inch cutting diameter with 0.2500 inch length of cut
• 2-flute helical geometry promotes chip evacuation in confined bore profiles
• No coolant-through design; suitable for external flood or mist coolant application

Compatibility

Designed for use on CNC machining centers capable of helical interpolation; accepts standard 1/4 inch shank toolholders including ER collet chucks and shrink-fit holders. Generates 4-40 UNC internal threads per the stated thread standard.

Installation Notes

Thread milling requires a CNC control capable of helical interpolation; verify control compatibility before programming. Secure the shank in a balanced, low-runout toolholder and confirm runout is within acceptable tolerance before cutting. Use appropriate flood or mist coolant directed at the cutting zone. Follow shop-specific speeds and feeds for the workpiece material and do not exceed the tool diameter or length-of-cut ratings stated by the manufacturer.