Osg 5320300 Square End Mill 0.25 in 3 Flute Cobalt

Product Description

The OSG 5320300 is a cobalt square end mill designed for milling operations in ferrous and difficult-to-machine materials. Built from M42 cobalt high-speed steel, this double-end tool delivers consistent cutting performance across both ends, extending tool life and reducing cost per edge. The cutter features a 0.25-inch diameter, a 0.625-inch length of cut, and a 30-degree helix angle that promotes smooth chip evacuation in a wide range of milling applications. With three spiral flutes and a right-hand cut and right-hand flute configuration, the 5320300 is suited for slot milling, profiling, and peripheral milling on manual and CNC machine tools. It is centercutting, allowing direct plunge entry into the workpiece.

This end mill fits production and job-shop environments where cobalt tooling is specified for its superior heat resistance and toughness compared to standard HSS. The 3/8-inch shank diameter and 3-3/8-inch overall length make it compatible with standard collet chucks and end mill holders commonly found on knee mills, bed mills, and CNC machining centers. It is a regular-length tool in the OSG Series 532 line, making it a direct drop-in for shops already standardized on that series. The uncoated finish is appropriate for use with cutting fluids and for materials where coated tooling may cause adhesion or built-up edge issues.

Key Features

• M42 cobalt construction for improved heat resistance and edge retention over standard HSS
• Double-end design provides two usable cutting ends per tool
• 30-degree helix angle supports efficient chip evacuation in slot and profile milling
• Centercutting geometry allows direct plunge cuts without pre-drilling
• Three spiral flutes with right-hand cut and right-hand flute configuration
• Uncoated finish compatible with flood coolant and cutting oil applications

Compatibility

Designed as an OEM-style replacement and standard tooling option within the OSG Series 532 end mill line. Fits any end mill holder or collet accepting a 3/8-inch shank diameter.

Installation Notes

Installation is performed by a machinist or tooling technician. Secure the 3/8-inch shank in a properly sized collet or end mill holder and torque the holder to machine-tool manufacturer specifications before engaging the spindle. Inspect both cutting ends for chips or damage before use, and confirm runout with a dial indicator when close-tolerance work is required. Always bring spindle to full speed before engaging the workpiece, and apply appropriate cutting fluid for the material being machined.