Robbjack SR-2-055 Square End Mill 0.055 in 2 Flute Carbide

Product Description

The ROBBJACK SR-2-055 is a square end mill from the SR-2 series, designed for precision milling in tight geometries and small-feature applications. The tool features a 0.055-inch cutting diameter with a 0.165-inch length of cut and a 1/8-inch straight cylindrical shank. Overall length is 1.5 inches. Constructed from solid carbide in the Tuffy material grade, it delivers the rigidity and edge retention needed for demanding cuts in steel, aluminum, and similar materials. With two flutes and an uncoated finish, this tool is suited for applications where sharp edges and fine chip evacuation are priorities.

This end mill is used in CNC machining centers and manual milling operations where small-diameter, high-precision cutting is required. The 0.055-inch diameter makes it well-suited for slot milling, profiling, and pocketing of miniature features in mold work, medical components, aerospace parts, and electronics fixtures. The centercutting geometry allows direct plunge entry. Right-hand cut and right-hand spiral flute configuration follow standard CNC toolpath conventions.

Key Features

• 0.055-inch cutting diameter with plus or minus 0.0005-inch diameter tolerance for close-tolerance work
• Solid carbide Tuffy grade construction for rigidity and wear resistance in small-diameter tools
• Centercutting design allows plunge milling without a pre-drilled entry point
• 30-degree helix angle with spiral flute for smooth chip evacuation
• Uncoated finish suitable for applications where coating-induced edge radius is unacceptable
• Right-hand cut, right-hand flute - compatible with standard CNC spindle rotation

Compatibility

Designed as an OEM-style replacement or direct-use tooling for CNC machining centers and manual mills accepting a 1/8-inch straight cylindrical shank collet or end mill holder.

Installation Notes

This tool is installed and changed by machinists or CNC setup technicians. Ensure the spindle is fully stopped and locked before installing or removing the end mill. Use a calibrated collet or end mill holder rated for 1/8-inch shank diameter and verify runout with a dial indicator before cutting. At 0.055-inch diameter, the tool is highly susceptible to breakage from side load, vibration, or improper feed rates - follow manufacturer cutting data for this diameter and material combination.