Accupro 311258 Corner Radius End Mill 1/4 in 4 Flute Alcrtin

Product Description

The ACCUPRO 311258 is a solid carbide corner radius end mill designed for precision milling operations in metalworking and machining environments. It features a 1/4 inch mill diameter, a 1 inch length of cut, and a 3 inch overall length. The AlCrTiN coating provides heat and oxidation resistance, extending tool life in demanding cutting conditions. With a 0.020 inch corner radius and a 38-degree helix angle, the 311258 delivers smooth chip evacuation and reduced chatter during interrupted cuts. It is a center-cutting, single-end tool with four flutes and a right-hand cutting direction. Machinists and CNC operators in job shops and production environments install this tool for profiling, slotting, and finishing passes on hardened and alloy steels.

This end mill is suited for use on vertical and horizontal CNC machining centers as well as manual knee mills where corner radius geometry is required to blend radii into part features. The variable index flute spacing reduces harmonic vibration during high-speed passes, making it a practical choice for finishing operations on ferrous and high-temperature alloy workpieces. The 1/4 inch shank diameter fits standard ER and milling collets common across most CNC toolholding systems. A chipbreaker geometry further aids chip management during longer cuts in deep-pocket or full-slot applications.

Key Features

• AlCrTiN coating resists heat and oxidation for extended tool life in hardened materials
• 0.020 inch corner radius blends radii into part features without secondary operations
• Four-flute, right-hand spiral design provides rigidity and efficient chip removal
• Center-cutting geometry allows direct plunge entry into workpiece material
• Variable index flute spacing reduces vibration and chatter during profiling passes
• Micrograin solid carbide construction maintains edge integrity at elevated cutting speeds

Compatibility

Designed as a direct-fit replacement for 1/4 inch shank corner radius end mills used in standard ER collets, milling chucks, and shrink-fit toolholders on CNC machining centers and manual mills.

Installation Notes

Installation is performed by qualified machinists or CNC setup technicians. Ensure the machine spindle is powered down and at a complete stop before changing tooling. Seat the 1/4 inch shank fully into the collet or toolholder and torque the retention nut per the toolholder manufacturer specification. Verify tool runout with a dial indicator before beginning a production run to confirm proper seating and minimize premature edge wear.