Hertel E2034040 Square End Mill 5/8 in 4 Flute Cobalt

Product Description

The HERTEL E2034040 is a 4-flute cobalt square end mill designed for general-purpose milling in ferrous and stainless materials. Built from M42 cobalt high-speed steel, it maintains cutting-edge hardness at elevated temperatures — a key advantage when machining work-hardening alloys. The 5/8 inch diameter matches the shank diameter, making tool holding straightforward in standard collets or end mill holders. With a 2.5 inch length of cut and a 4-5/8 inch overall length, this is a long-series tool suited for deeper axial cuts where a standard-length end mill would fall short. The 30-degree helix and right-hand spiral flute geometry promote smooth chip evacuation in peripheral and slot milling operations. Arrives uncoated and ready to run.

This end mill is used in manual knee mills, CNC machining centers, and toolroom applications where cobalt HSS is preferred over carbide due to interrupted cuts, flexible setups, or material characteristics that favor toughness over pure hardness. The long-series geometry makes it well-suited for reaching into pockets, clearing fixtures, or milling stepped features that require extended projection from the spindle. Right-hand cut and right-hand flute configuration is standard for conventional and climb milling on right-hand spindle machines. Note that this is a non-centercutting design, so it is not intended for direct plunge entry.

Key Features

• M42 cobalt high-speed steel construction resists heat buildup in tough alloys
• 4-flute configuration balances chip load and surface finish in ferrous materials
• Long-series length of cut at 2.5 inches for deep pocket and extended-reach applications
• 30-degree helix angle promotes smooth chip flow and reduced cutting forces
• Right-hand cut, right-hand flute — standard orientation for conventional spindle machines
• Uncoated finish allows regrinding and is compatible with cutting fluids and oils
• Non-centercutting — requires a pre-drilled or pre-bored entry point for plunge operations

Compatibility

Designed as an OEM-style replacement or direct-use end mill for machines accepting a 5/8 inch straight shank, including standard ER collet chucks, Weldon-style end mill holders, and hydraulic or shrink-fit toolholders bored to 5/8 inch.

Installation Notes

Installation and tool changes must be performed with the machine spindle fully stopped and locked out per shop lockout/tagout procedures. Seat the shank fully into the holder and torque the retention mechanism to the toolholder manufacturer's specification. Verify runout with a dial indicator before cutting, as excessive runout accelerates edge wear on cobalt HSS tools. A licensed machinist or qualified CNC operator should confirm speeds, feeds, and depth-of-cut parameters based on workpiece material and machine rigidity before engaging the cut.