Hertel E4040016 Square End Mill 1/4 in 4 Flute Cobalt Tin

Product Description

The HERTEL E4040016 is a cobalt square end mill designed for precision milling operations in ferrous and non-ferrous materials. Built from M42 cobalt high-speed steel, it delivers superior heat and wear resistance compared to standard HSS tooling. The 4-flute, spiral design with a 30-degree helix angle promotes efficient chip evacuation and smooth cutting action. A titanium nitride (TiN) finish reduces friction and extends tool life. This is a centercutting end mill, meaning it can plunge directly into workpiece material as well as perform peripheral and slot milling. It is installed and used by machinists and tool-and-die professionals in manual and CNC milling applications.

The E4040016 fits general-purpose milling on machining centers, knee mills, and CNC mills. With a 0.25-inch mill diameter and a 1.25-inch length of cut, it is well suited for slotting, profiling, and finishing passes in steel, stainless, cast iron, and high-temperature alloys where cobalt tooling outperforms standard HSS. The long-series geometry provides additional reach for deeper pockets and stepped features without tool holder interference.

Key Features

• M42 cobalt HSS construction for elevated heat resistance during aggressive cuts
• TiN coating reduces friction and extends cutting edge life
• 4-flute spiral geometry with 30-degree helix for balanced chip load and smooth finish
• Centercutting design allows direct plunge entry into the workpiece
• Right-hand cut, right-hand flute configuration for standard milling setups
• Long-series length type provides additional reach for deep pockets and stepped features

Compatibility

Designed as an OEM-style replacement or direct-application end mill compatible with standard 3/8-inch ID end mill holders, collet chucks, and milling machine spindles accepting a 0.375-inch shank diameter.

Installation Notes

This end mill is installed by machinists using a compatible end mill holder or collet rated for the 0.375-inch shank diameter. Ensure the machine spindle is fully stopped and locked out before tool changes. Proper runout should be verified with a dial indicator after seating to prevent premature edge wear or tool breakage. Follow machine manufacturer feed and speed recommendations for cobalt tooling when establishing cutting parameters.