Osg 5401505 Square End Mill 3/4 in 4 Flute Cobalt Tin

Product Description

The OSG 5401505 is a 4-flute cobalt square end mill designed for milling ferrous and hard materials in machining centers and manual mills. Built from M42 cobalt high-speed steel and finished with a titanium nitride (TiN) coating, it delivers improved wear resistance and heat tolerance compared to standard HSS tooling. The cutter runs at 0.75 inches in diameter with a 1.625-inch length of cut and a 0.50-inch shank diameter, making it a regular-length tool suited to general-purpose slotting, profiling, and peripheral milling. It is intended for use by machinists and tool-and-die professionals in production or job-shop environments.

The 5401505 belongs to OSG Series 540, a line of cobalt end mills configured for right-hand cut with right-hand spiral flutes at a 30-degree helix angle. The spiral flute geometry promotes smooth chip evacuation during side milling operations. This is a single-end, non-centercutting tool, so it is not suited for direct plunge cuts. Typical applications include step milling, shoulder milling, and contouring on steel, stainless, and other ferrous workpieces where TiN-coated cobalt tooling is specified.

Key Features

• M42 cobalt HSS construction for elevated heat and wear resistance
• TiN coating reduces friction and extends tool life in ferrous materials
• 30-degree helix spiral flute for efficient chip evacuation
• 4-flute configuration provides good surface finish and feed rate capability
• Right-hand cut, right-hand flute — standard spindle rotation compatible
• Non-centercutting design; ramp or helical entry required for plunge-in operations

Compatibility

Designed as an OEM-style replacement or direct-fit tool for milling applications requiring a 3/4-inch diameter, 4-flute cobalt square end mill with a 1/2-inch shank, consistent with OSG Series 540 specifications.

Installation Notes

Installation is performed by a qualified machinist or toolroom professional. Secure the shank in a collet, end mill holder, or side-lock holder rated for the shank diameter before operation; verify runout with a dial indicator before cutting. Always power down and lock out the spindle before changing tooling. Follow applicable OSHA machining safety standards and the machine tool manufacturer's speed and feed guidelines for cobalt end mills.