Osg 5420105 Square End Mill 1/8 in 4 Flute Cobalt Tin

Product Description

The OSG 5420105 is a cobalt square end mill designed for precision milling in ferrous and abrasive materials. Built from M42 high-speed cobalt steel and finished with a titanium nitride (TiN) coating, this tool delivers extended wear resistance and heat tolerance in demanding cutting environments. The double-end configuration provides two usable cutting ends, extending overall tool life per unit. With a 0.125 inch cutting diameter, four flutes, a 30-degree helix angle, and a right-hand spiral flute pattern, this end mill is suited for general-purpose slotting, profiling, and peripheral milling. Machinists and toolroom operators working with steel, stainless, and cast iron will find this tool appropriate for both manual and CNC milling setups.

This end mill is used in metalworking applications where a small-diameter, multi-flute tool is required for fine detail work, narrow slot cutting, or finishing passes. The 3/8 inch shank fits standard collets and end mill holders across a wide range of vertical mills and machining centers. The regular length-of-cut classification and 3-1/16 inch overall length make it appropriate for setups where toolholder clearance is standard and extended reach is not needed. It is commonly used in job shops, tool and die operations, and production machining environments.

Key Features

• M42 cobalt steel construction for high red hardness and wear resistance in tough alloys
• TiN finish reduces friction and extends tool life in ferrous applications
• Double-end design provides two cutting ends per tool
• 30-degree helix angle promotes smooth chip evacuation and reduced cutting forces
• Right-hand cut, right-hand flute spiral pattern for standard milling operations
• Four flutes for improved surface finish and feed rate capability over two-flute designs

Compatibility

Designed as an OEM-style cutting tool for use with standard 3/8 inch collets and end mill holders on vertical milling machines and CNC machining centers. Part of the OSG Series 542 cobalt end mill line.

Installation Notes

Installation should be performed by a qualified machinist following shop safety procedures. Ensure the spindle is fully stopped and locked out before mounting or removing the tool. Seat the shank fully in the collet or holder to the recommended engagement depth and torque the retention hardware per the toolholder manufacturer specifications. Confirm runout with a dial indicator before beginning the cut, particularly for finish-milling applications where dimensional accuracy is critical.