Osg 5270300 Square End Mill 1/4 in 2 Flute Cobalt

Product Description

The OSG 5270300 is a cobalt square end mill designed for milling operations in metalworking and machining environments. Built from M42 cobalt high-speed steel, it offers improved heat and wear resistance compared to standard HSS tooling, making it suitable for harder workpiece materials and demanding cutting conditions. The cutter measures 0.25 inches in diameter with a 0.625-inch length of cut and a 0.375-inch shank diameter. A 30-degree helix angle promotes smooth chip evacuation and reduces cutting forces. This tool is used by machinists and tool-and-die professionals operating manual or CNC milling machines.

The OSG 5270300 fits standard milling machine spindles and CNC machining centers that accept a 0.375-inch shank. Its extended reach design, with a 1.5-inch reach length and 3.0625-inch overall length, allows access to deeper features and stepped profiles that shorter tooling cannot reach. The center-cutting geometry permits direct plunge entry into the workpiece without a pre-drilled pilot hole. Right-hand cut with right-hand spiral flutes is the standard configuration for conventional and climb milling on most vertical and horizontal milling setups.

Key Features

• M42 cobalt construction provides elevated red hardness and wear resistance for harder alloys and stainless steels
• Center-cutting geometry allows direct plunge milling without a pilot hole
• 30-degree helix angle promotes efficient chip flow and reduces heat buildup at the cutting edge
• Extended reach with 1.5-inch reach length suits deep-pocket and stepped-profile milling
• Uncoated finish allows straightforward resharpening and is compatible with cutting fluids
• Right-hand cut, right-hand flute spiral configuration suits standard milling machine setups

Compatibility

Designed as a standard replacement or first-fit cobalt square end mill for milling machines and CNC machining centers that accept a 0.375-inch shank diameter. Part of OSG Series 527.

Installation Notes

Installation should be performed by a qualified machinist with the spindle fully stopped and the machine powered down before tool changes. Secure the shank in a collet or end mill holder to the depth recommended by the toolholder manufacturer, ensuring adequate engagement without bottoming out. Confirm runout with a dial indicator before beginning a cut. Follow applicable shop safety practices and machine manufacturer guidelines for speeds and feeds based on workpiece material.