Osg HP421-0394 Square End Mill 0.0394 in 2 Flute Carbide

Product Description

The OSG HP421-0394 is a solid carbide square end mill designed for precision milling in demanding machining environments. With a 0.0394 inch (1.00 mm) cutting diameter and a 0.1181 inch (3.00 mm) length of cut, this tool is built for micro-scale material removal where accuracy is critical. The two-flute spiral geometry and 35-degree helix angle promote efficient chip evacuation and reduce cutting forces. A TiAlN (titanium aluminum nitride) coating improves heat resistance and extends tool life in hard and abrasive workpiece materials. Machinists and CNC operators working on precision components, molds, and fine-detail part features will find this end mill suited to tight-tolerance applications.

This end mill fits standard CNC machining center operations requiring a small-diameter, centercutting tool. The 3.00 mm shank diameter and 39.00 mm overall length make it compatible with common collet systems used in vertical machining centers and high-speed spindles. It is appropriate for slotting, profiling, and plunge-entry cuts in ferrous and non-ferrous metals. The right-hand cut and right-hand flute configuration follow standard conventions for the majority of CNC setups. The HP421 series from OSG targets high-performance micro-milling applications where tool rigidity and coating durability are priorities.

Key Features

• 0.0394 inch (1.00 mm) cutting diameter for micro-scale milling operations
• Solid carbide micrograin construction for rigidity and wear resistance
• TiAlN coating for improved heat resistance in hard materials
• 35-degree helix angle with spiral flute geometry for efficient chip flow
• Centercutting design allows direct plunge entry into the workpiece
• Right-hand cut and right-hand flute — standard CNC orientation

Compatibility

Designed for use in CNC machining centers and high-speed spindles accepting a 3.00 mm shank diameter; part of the OSG HP421 series for high-performance micro-milling applications.

Installation Notes

Installation should be performed by a qualified machinist or CNC setup technician. Ensure the spindle is fully stopped and the machine is in a safe state before tool changes. Use a properly sized collet or tool holder matched to the 3.00 mm shank to prevent runout. Confirm runout within acceptable tolerance before engaging the cut, as excessive runout on small-diameter carbide tools can cause immediate tool failure.