Osg HP441-8661 Square End Mill 0.8661 in 4 Flute Carbide

Product Description

The OSG HP441-8661 is a solid carbide square end mill designed for high-performance milling operations in metalworking and machining environments. It features a 0.8661-inch (22 mm) mill diameter with a 1.4961-inch (38 mm) length of cut, four spiral flutes ground to a 35-degree helix angle, and a TiAlN coating that extends tool life at elevated cutting temperatures. The micrograin carbide substrate provides edge retention and resistance to chipping under demanding cutting conditions. This is a centercutting tool, allowing both plunge and lateral entry. It is sized for use in CNC machining centers, manual mills, and horizontal milling setups where rigidity and tool life are priorities.

The HP441-8661 is suited for milling ferrous and non-ferrous metals, including hardened steels, alloy steels, and cast iron, where TiAlN coatings perform well at high surface speeds. The 35-degree helix angle balances chip evacuation with cutting stability, making it appropriate for slotting, profiling, and pocket milling operations. Right-hand cut and right-hand flute geometry follow standard CNC spindle conventions. This tool is part of the OSG HP441 series, which targets production machining environments where consistent tool performance and repeatability are required.

Key Features

• 0.8661-inch (22 mm) mill diameter with 1.4961-inch (38 mm) length of cut
• Solid micrograin carbide construction for edge retention and dimensional stability
• TiAlN finish extends tool life under high-speed and dry cutting conditions
• 35-degree helix angle promotes efficient chip evacuation in spiral flute geometry
• Centercutting design allows direct plunge entry without pre-drilling
• Right-hand cut, right-hand flute — compatible with standard CNC spindle rotation

Compatibility

Designed as an OEM-style replacement or direct fitment for applications requiring a 22 mm shank diameter square end mill in the OSG HP441 series. Confirm spindle taper, collet size, and tool holder bore before installation.

Installation Notes

Installation is performed by qualified machinists or CNC setup technicians. Ensure the spindle and tool holder are clean and free of chips before seating the tool. Torque collet nuts or set screws according to the tool holder manufacturer specifications — do not use values not provided with your specific holder. Verify runout with a dial indicator after clamping before initiating a cut.