Helical Solutions 86839 Corner Radius End Mill 1/4 in 6 Flute

Product Description

The HELICAL SOLUTIONS 86839 is a 6-flute, solid carbide corner radius end mill designed for high-performance material removal in demanding machining applications. Built on the HEV-RN-6 series platform, it features a 0.50 mm (0.0200 inch) corner radius, a 1/4 inch cutting diameter, and a 3/8 inch length of cut. The Tplus PVD coating extends tool life when cutting abrasive and work-hardening materials. Variable pitch geometry reduces harmonic vibration during aggressive cuts. This tool handles both roughing and finishing operations in a single setup, making it a practical choice for machinists and tooling specialists working in precision job shops or production environments.

The 86839 is engineered for cutting stainless steel, high-temperature alloys, and hardened steels — material groups classified as M, S, and H. The extended reach design, with a 1-1/8 inch reach length and 0.2370 inch neck diameter, allows access to deeper features without sacrificing rigidity. The straight-cylindrical shank is sized at 1/4 inch with an h6 tolerance, making it compatible with high precision toolholders. It is a single-end, centercutting tool with right-hand flute direction and right-hand cutting direction, suitable for standard vertical and horizontal CNC machining centers.

Key Features

• 6-flute variable pitch geometry reduces chatter and supports aggressive feed rates
• Tplus PVD coating improves wear resistance in stainless steel and high-temp alloys
• 0.50 mm corner radius (0.0200 inch) blends strength at the cutting edge and reduces chipping
• Extended reach with 1-1/8 inch reach length and reduced 0.2370 inch neck diameter for deep-feature access
• Centercutting design allows plunge entry without a pre-drilled pilot hole
• Solid carbide construction provides stiffness and dimensional stability at elevated cutting temperatures

Compatibility

Designed for use with high precision toolholders. Straight-cylindrical 1/4 inch shank with h6 tolerance fits standard precision collet chucks and shrink-fit holders used on CNC machining centers.

Installation Notes

Installation should be performed by a qualified machinist or tooling technician. Ensure the machine spindle is fully stopped and locked out before changing tooling. Seat the shank to the recommended gauge length for your toolholder and verify runout with a dial indicator — maximum TIR for this tool is 0.0005 inch. Use high precision toolholders as specified to maintain tolerances and prevent premature tool wear.