Hertel E2039904 Square End Mill 1 Inch Cobalt 4 Flute

Product Description

The HERTEL E2039904 is a cobalt square end mill designed for milling operations in ferrous and difficult-to-machine materials. With a 1 inch cutting diameter and 4 spiral flutes ground to a 30-degree helix angle, this tool delivers efficient chip evacuation and a stable cut. The 1.875-inch length of cut (LOC) suits slotting, profiling, and peripheral milling tasks. It is a centercutting design, allowing plunge entry without a pre-drilled hole. Built from M42 cobalt high-speed steel, the E2039904 runs uncoated and is intended for use by machinists and tool-and-die professionals on manual mills and CNC machining centers.

This end mill is suited for general-purpose material removal in job shop, maintenance, and production environments. The right-hand cut and right-hand spiral flute configuration is standard for conventional milling setups. The 0.75 inch shank diameter fits common ER and straight-bore toolholders found on knee mills and vertical machining centers. The regular-length geometry keeps the tool rigid, reducing deflection during interrupted cuts or high-feed passes on steel, stainless, and cast iron workpieces.

Key Features

• 1 inch cutting diameter with 1.875-inch length of cut for versatile depth capability
• M42 cobalt construction provides heat and wear resistance in tough alloys
• 30-degree spiral helix promotes smooth cutting action and positive chip flow
• Centercutting geometry allows direct plunge entry into the workpiece
• Right-hand cut, right-hand flute — standard orientation for conventional mill setups
• Uncoated finish suitable for re-sharpening and cost-effective regrind cycles

Compatibility

Designed as a standard straight-shank square end mill compatible with 3/4 inch collet chucks, ER toolholders, and straight-bore end mill holders used on vertical knee mills and CNC machining centers.

Installation Notes

Installation is performed by qualified machinists. Ensure the machine spindle is fully stopped and locked out before changing tooling. Seat the 0.75 inch shank fully into the holder to the recommended engagement depth before tightening the collet or set screw. Verify runout with a dial indicator after mounting to minimize premature edge wear.