Osg 5484100 Square End Mill 3/4 Inch 4 Flute Cobalt

Product Description

The OSG 5484100 is a 4-flute cobalt square end mill designed for high-performance milling in ferrous and hardened materials. Built to Series 548 specifications, it features a 3/4 inch cutting diameter, a 2-1/4 inch length of cut, and a 4-1/2 inch overall length with a matched 3/4 inch straight shank. The cobalt construction — M42 grade — delivers superior heat resistance and edge retention compared to standard high-speed steel, making it a reliable choice for interrupted cuts, stainless steels, and heat-resistant alloys. The 30-degree helix angle promotes efficient chip evacuation and smooth cutting action across a range of materials.

This end mill is suited for general-purpose and production milling operations in machine shops, toolrooms, and manufacturing environments. It handles shoulder milling, slotting, and peripheral profiling on vertical and horizontal machining centers as well as manual knee mills. The centercutting geometry allows direct plunge entry, adding flexibility when programming ramp or plunge moves without a separate drill operation. This tool is a single-end, uncoated configuration intended for shops that prefer to regrind or apply their own coatings.

Key Features

• M42 cobalt construction for improved red hardness and edge retention over standard HSS
• 30-degree right-hand spiral flute promotes efficient chip flow and reduced chatter
• Centercutting design enables direct plunge cutting without a pilot hole
• 4 flutes provide a good balance of chip clearance and surface finish capability
• Uncoated finish allows straightforward regrinding and optional custom coating
• Matched 3/4 inch shank and cutter diameter for use in standard ER or side-lock holders

Compatibility

Designed as an OEM-style replacement or direct-use tooling for standard 3/4 inch end mill holders, collet chucks, and milling arbors used in vertical machining centers, CNC knee mills, and manual milling machines accepting straight-shank tooling.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician. Ensure the machine spindle is fully stopped and the tool holder is clean and free of debris before seating the shank. Torque the set screw or collet nut according to the holder manufacturer specifications. Verify runout at the cutting end with a dial indicator before beginning any cut to maximize tool life and surface finish quality.