Accupro 311250 Corner Radius End Mill 1/4 in Carbide

Product Description

The ACCUPRO 311250 is a solid carbide corner radius end mill designed for precision milling operations in ferrous and hardened materials. It features a 1/4 inch diameter with a 1/2 inch length of cut and a 2-1/2 inch overall length. The four-flute, single-end geometry with a 38-degree helix angle promotes efficient chip evacuation and smooth cutting action. An AlCrTiN coating provides thermal resistance and extended tool life in high-speed applications. The micrograin carbide substrate and variable index design reduce chatter and improve surface finish. This tool is centercutting, allowing plunge entry. It is installed and used by machinists and tool-and-die professionals on CNC milling machines and machining centers.

The 311250 is suited for profiling, slotting, and contouring operations in precision machining environments. Its corner radius geometry — 0.020 inch radius — reduces stress concentration at the cutting edge and produces a controlled radius at inside corners. The right-hand flute direction and right-hand cutting rotation make it compatible with standard CNC spindle configurations. It is appropriate for use in mold-making, die work, aerospace component machining, and general precision part production where edge integrity and surface finish are critical.

Key Features

• Solid micrograin carbide substrate for rigidity and wear resistance in demanding cuts
• AlCrTiN coating for high-temperature performance and extended tool life
• Four-flute, centercutting design allows plunge milling entry
• Variable index geometry reduces harmonic vibration and chatter
• 0.020 inch corner radius reduces edge stress and produces consistent inside corner geometry
• 38-degree helix angle promotes efficient chip evacuation and smooth cutting action
• Chipbreaker geometry included for improved chip management in deep cuts

Compatibility

Designed as an OEM-style solid carbide corner radius end mill for use in standard 1/4 inch collets and end mill holders on CNC milling machines and machining centers with right-hand spindle rotation.

Installation Notes

Installation is performed by a qualified machinist or CNC setup technician. Ensure the machine spindle is fully stopped and locked out before inserting or removing the tool from the holder. Use a calibrated torque wrench and appropriate collet or set-screw holder rated for 1/4 inch shank tooling. Verify tool runout with a dial indicator after installation and before initiating any cutting cycle to protect both the workpiece and the tool edge.