Hertel E199921279 Square End Mill 25/64 in 2 Flute Hss

Product Description

The HERTEL E199921279 is a single-end, square-profile end mill manufactured from high speed steel (HSS) and designed for general-purpose milling operations in machine shop and production environments. The cutter measures 0.3906 inches (25/64 inches) in diameter with a 13/16-inch length of cut and a 2-11/16-inch overall length. Two right-hand spiral flutes at a 30-degree helix angle provide efficient chip evacuation and a balanced cut. The bright, uncoated finish makes it straightforward to inspect for wear. This tool is installed and operated by machinists, tool-and-die makers, and CNC setup technicians working on mills, machining centers, and manual knee mills.

This end mill is suited for slotting, profiling, and peripheral milling in ferrous and non-ferrous materials where an HSS cutter is appropriate. The centercutting geometry allows the tool to plunge directly into a workpiece, making it effective for cavity work and pocketing operations. The 3/8-inch shank diameter fits standard ER collets, end mill holders, and Weldon-style tool holders commonly found in light-to-medium duty machining setups. It is a practical choice for short-run jobs, tool room work, and situations where carbide tooling is not required.

Key Features

• 25/64-inch (0.3906 inches) cutting diameter with square end profile
• 2 right-hand spiral flutes with 30-degree helix angle for efficient chip flow
• Centercutting design supports direct plunge entry
• High speed steel construction — suitable for a broad range of workpiece materials
• Bright/uncoated finish for easy visual wear inspection
• Single-end configuration; 3/8-inch shank fits standard collet and end mill holders

Compatibility

Designed as a standard single-end square end mill with a 3/8-inch shank diameter, compatible with ER collets, Weldon-style end mill holders, and other 3/8-inch bore toolholding systems used on vertical and horizontal milling machines and CNC machining centers.

Installation Notes

Installation should be performed by a qualified machinist following shop safety procedures. Ensure the spindle is fully powered down and locked out before mounting or removing the tool. Verify collet or holder bore size matches the 3/8-inch shank before tightening; proper tool stick-out should be minimized to reduce deflection. Confirm spindle rotation direction is set to right-hand before engaging the cut.