Osg 5403100 Square End Mill 3/4 in 4 Flute Cobalt

Product Description

The OSG 5403100 is a square end mill designed for general-purpose milling operations in metal fabrication and machining environments. Built from M42 cobalt high-speed steel, it delivers strong heat and wear resistance when cutting ferrous and non-ferrous materials. The tool features a 0.75 inch mill diameter, a 1.625 inch length of cut, and a 3.875 inch overall length. With four spiral flutes and a 30-degree helix angle, it produces efficient chip evacuation and smooth cutting action. Licensed machinists and tool-and-die technicians are the primary installers and operators of this end mill.

This end mill is suited for side milling, slotting, and profiling operations on machining centers and manual vertical mills. The regular length classification makes it appropriate for standard-depth cuts in steel, stainless, cast iron, and similar materials. The 0.75 inch shank diameter fits standard R8, CAT, BT, and HSK toolholders with a matching bore. It belongs to OSG Series 540, a cobalt end mill line intended for general production machining where carbide tooling is not required or cost-justified.

Key Features

• M42 cobalt construction for elevated heat resistance compared to standard HSS
• 30-degree helix angle with spiral flutes for efficient chip removal
• Four flutes for a balance of chip clearance and surface finish
• Right-hand cut and right-hand flute configuration for standard spindle operation
• Uncoated finish — suitable for re-sharpening and general-purpose applications
• Non-centercutting geometry — not intended for direct plunge entry

Compatibility

Designed as a general-purpose replacement or production end mill for use with 0.75 inch bore toolholders on vertical machining centers and manual knee mills; belongs to OSG Series 540.

Installation Notes

Installation is performed by a qualified machinist or CNC setup technician. Ensure the spindle is fully stopped and the machine is powered down before changing tooling. Use a properly sized collet or end mill holder matching the 0.75 inch shank diameter and torque to the toolholder manufacturer's specification. This tool is non-centercutting and must be ramped or helically interpolated into the workpiece rather than plunged directly.