Kennametal 3899138 Corner Radius End Mill 3/8 in 5 Flute

Product Description

The KENNAMETAL 3899138 is a solid carbide corner radius end mill designed for high-performance milling in demanding materials. It features a 3/8 inch diameter, a 0.03 inch corner radius, and five flutes ground to a high-helix spiral configuration. The AlTiN (aluminum titanium nitride) PVD coating provides elevated heat and wear resistance, making this tool well-suited for dry or semi-dry cutting. With a 1 inch length of cut and 3 inch overall length, the 3899138 handles both roughing and finishing passes in a single-end configuration. It is intended for use by machinists and tooling professionals in CNC milling operations.

This end mill is rated for cutting steel, stainless steel, cast iron, superalloys, titanium, and hard materials, covering ISO material codes P, M, K, S, and H. It belongs to KENNAMETAL's UCDE series and is manufactured from submicron-grade solid carbide. The straight cylindrical shank at 3/8 inch diameter is compatible with HC 20M through HC 32M hydraulic sleeves (metric with inch bores). It is suited for precision milling centers operating in job shops, aerospace, die and mold, and general metalworking environments.

Key Features

• Solid carbide construction with submicron-grade material for edge retention in hard workpieces
• AlTiN PVD coating provides thermal resistance and extended tool life in abrasive cuts
• 0.03 inch corner radius reduces stress concentration and improves surface finish at part edges
• Five-flute, high-helix spiral geometry supports both roughing and finishing in a single tool
• Right-hand cut and right-hand flute direction for standard CNC milling spindle compatibility
• Normal pitch, non-chipbreaker design optimized for controlled chip evacuation on ferrous and hard materials

Compatibility

Compatible with HC 20M through HC 32M hydraulic sleeves (metric with inch bores). The 3/8 inch straight cylindrical shank fits standard collet chucks and hydraulic tool holders accepting that shank diameter. Rated for steel, stainless steel, cast iron, superalloys and titanium, and hard materials.

Installation Notes

Installation should be performed by a qualified machinist or tooling technician. Ensure the spindle is fully stopped and the machine is in a safe state before inserting or removing the end mill. Seat the shank to the full recommended engagement depth in the tool holder and verify runout with a dial indicator before cutting. Follow the tool manufacturer's recommended speeds and feeds for the specific workpiece material and coating type.