Accupro C911-56212 Thread Mill 9/16-12 Internal Carbide

Product Description

The ACCUPRO C911-56212 is a helical flute thread mill designed for cutting internal 9/16-12 UNC threads in a single helical pass. Built from micrograin solid carbide, this 4-flute tool offers the rigidity and edge retention needed for threading hardened or abrasive workpiece materials. The cutting diameter measures 0.45 inches, the length of cut is 0.875 inches, and the 0.5-inch straight shank fits standard milling chucks and collet holders. A TiAlN coating reduces heat buildup and extends tool life in dry or light-coolant applications. This tool is used by machinists and tool-and-die professionals running CNC machining centers where thread milling is preferred over tapping.

Thread milling with the C911-56212 is suited for CNC vertical and horizontal machining centers producing 9/16-12 UNC internal threads. The helical flute geometry and right-hand flute direction make this tool appropriate for through-hole and blind-hole threading operations where a single-point or tap-based approach is not preferred. The 12 teeth-per-inch pitch matches the UNC standard for 9/16-inch nominal diameter fastener threads. This tool is a fit for production environments, job shops, and toolrooms working in steel, cast iron, stainless, and similar materials where micrograin carbide performs reliably.

Key Features

• Micrograin solid carbide construction for edge retention in tough materials
• TiAlN coating reduces friction and extends tool life in elevated-temperature cuts
• 4-flute helical design for efficient chip evacuation during internal thread milling
• Right-hand flute direction compatible with standard CNC spindle rotation
• 0.45-inch cutting diameter and 0.875-inch length of cut sized for 9/16-12 UNC threads
• No coolant-through requirement — suitable for external flood or dry cutting setups

Compatibility

Designed for CNC machining centers using standard 0.5-inch collet or milling chuck toolholders, cutting 9/16-12 UNC internal threads per the UNC thread standard.

Installation Notes

Installation is performed by qualified machinists or CNC setup technicians. Secure the 0.5-inch shank in a balanced collet holder or milling chuck to the toolholder manufacturer's specified clamping torque — do not exceed shank diameter tolerances of 0.0003 inches. Program the CNC controller for helical interpolation using the correct thread pitch and cutting diameter offset before engaging the workpiece. Inspect the cutting edges before each use and do not run a chipped or worn tool, as carbide thread mills are brittle under side-load shock.