Osg 5426400 Square End Mill 17/64 in 4 Flute Cobalt

Product Description

The OSG 5426400 is a cobalt square end mill designed for milling operations in ferrous and high-temperature alloy materials. Built from M42 cobalt high-speed steel, it delivers heat resistance and edge retention under demanding cutting conditions. The double-end configuration provides two usable cutting ends, extending tool life between replacements. With a 17/64 inch (0.2656 inch) cutting diameter, 4 spiral flutes, and a 30-degree helix angle, it produces efficient chip evacuation and a stable cut. The right-hand cut, right-hand flute geometry is standard for conventional vertical milling setups. This end mill is uncoated and suited for general-purpose slotting, profiling, and side milling in a machine shop environment.

The OSG 5426400 is used in CNC machining centers, knee mills, and manual vertical mills for slotting, pocketing, and peripheral milling. The 11/16 inch length of cut (0.6875 inch) handles moderate-depth passes in steel, stainless, cast iron, and similar materials. The 3/8 inch shank diameter fits standard ER and end mill holders commonly found in job shop and production environments. The regular-length Series 542 designation positions this tool for standard-reach applications without the deflection risk of extended-reach tooling.

Key Features

• M42 cobalt HSS construction for heat resistance and edge retention in tough alloys
• Double-end design provides two cutting ends per tool, maximizing value per tool
• 4 spiral flutes with 30-degree helix angle for efficient chip evacuation
• Right-hand cut and right-hand flute geometry for standard milling setups
• Not center-cutting — requires a pre-drilled hole for plunge entry
• Uncoated finish suitable for use with cutting fluids on ferrous materials

Compatibility

Designed as an OEM-style replacement or direct-use tooling for standard 3/8 inch end mill holders and collet chucks used in vertical milling applications.

Installation Notes

Installation is performed by a machinist or toolroom technician. Secure the 3/8 inch shank in a clean, properly sized end mill holder or collet to the manufacturer-specified torque for that holder type. Inspect the holder bore and collet for wear or contamination before seating the tool. Because this end mill is not center-cutting, do not plunge directly into solid material — use a pre-drilled entry point or ramp entry. Always confirm spindle direction matches the right-hand cut geometry before starting the machine.