Accupro 311789 Corner Radius End Mill 3/4 in 5 Flute

Product Description

The ACCUPRO 311789 is a single-end, corner radius end mill designed for precision milling operations in ferrous and hard alloy materials. Built from solid carbide micrograin substrate and coated with AlCrTiN, it delivers extended tool life at elevated cutting temperatures. The 3/4 inch diameter, 5-flute geometry with a 38-degree helix provides aggressive chip evacuation while maintaining a smooth surface finish. The 0.090 inch corner radius protects the cutting edge and reduces stress concentrations at the workpiece transition. This tool is installed and operated by machinists and CNC tooling technicians in job shop and production environments.

This end mill suits general and high-performance milling applications in steel, stainless, and hardened alloys. The 1-5/8 inch length of cut accommodates moderate-depth peripheral and slot milling passes. The centercutting design allows plunge entry, adding versatility in pocketing and contour operations. With a 4 inch overall length and 3/4 inch shank diameter, it mounts directly into standard ER or side-lock toolholders common in 3-axis and 5-axis CNC machining centers.

Key Features

• AlCrTiN coating resists heat and oxidation for longer tool life in hard and abrasive materials
• Solid carbide micrograin construction provides rigidity and edge retention
• 5-flute, right-hand spiral geometry with variable index for reduced harmonic chatter
• 0.090 inch corner radius protects cutting edges and reduces workpiece stress risers
• Centercutting capability allows direct plunge entry without pre-drilling
• 38-degree helix angle promotes efficient chip flow and improved surface finish

Compatibility

Designed as an OEM-style replacement and standard tooling option for CNC machining centers and manual mills accepting a 3/4 inch shank end mill holder.

Installation Notes

Installation and tool changes must be performed with the machine spindle fully stopped and control in an e-stop or locked-out state per applicable shop safety and OSHA lockout/tagout procedures. Seat the 3/4 inch shank fully into the toolholder and torque the retention mechanism to the toolholder manufacturer's specification — do not use an unmarked or worn collet. Verify runout at the tool tip with a dial indicator before initiating a cut. Confirm cutting parameters including feed rate, speed, and depth of cut against the material grade and toolpath before running the first part.