Osg 404-250005 Square End Mill 1/4 in 4 Flute Solid Carbide

Product Description

The OSG 404-250005 is a solid carbide square end mill designed for precision milling operations in metal, alloy, and composite workpiece materials. Built on OSG Series 404, it features a 0.2500 inch mill diameter with a 0.7500 inch length of cut and a 30-degree helix angle that promotes smooth chip evacuation and consistent cutting performance. The four-flute configuration increases feed capacity relative to two- and three-flute designs, making it well-suited for finishing passes and semi-finishing in ferrous and non-ferrous materials. A titanium nitride (TiN) coating adds surface hardness and reduces tool wear. This end mill is installed and operated by machinists and tool-and-die professionals on CNC machining centers and manual milling equipment.

This end mill is used in general-purpose milling applications including slotting, profiling, and peripheral milling on steel, stainless, aluminum, and similar materials. The centercutting geometry allows plunge cutting directly into the workpiece. The right-hand cut and right-hand spiral flute orientation are standard for conventional CNC spindle setups. The regular length configuration keeps deflection low during shoulder and slot milling operations. It is appropriate for job shop, production, and tool room environments where consistent dimensional accuracy is required.

Key Features

• Solid carbide micrograin construction for rigidity and edge retention
• TiN coating increases surface hardness and extends tool life
• 4-flute, spiral flute design for improved feed rates and finish quality
• 30-degree helix angle promotes efficient chip evacuation
• Centercutting capability allows direct plunge entry into the workpiece
• Right-hand cut, right-hand flute — standard orientation for CNC and manual mill setups

Compatibility

Designed as an OEM-style solid carbide square end mill replacement suitable for 1/4 inch collet or end mill holder setups on CNC machining centers and manual vertical milling machines.

Installation Notes

Installation and tool changes should be performed by a qualified machinist with the spindle fully stopped and the machine in a locked-out, de-energized state per OSHA lockout/tagout procedures. Seat the 1/4 inch shank securely in a properly sized collet or end mill holder and torque the retention hardware according to the toolholder manufacturer specifications. Inspect the cutting edges and coating for chips or damage before mounting. Do not exceed the recommended depth-of-cut or feed rate for the workpiece material and machine rigidity class.