Robbjack NR-204-10 Square End Mill 5/16 in 2 Flute Carbide

Product Description

The ROBBJACK NR-204-10 is a 2-flute, solid carbide square end mill designed for general-purpose milling operations in metalworking and machining environments. Built to Series NR-204 standards, it features a 5/16 inch diameter with a matching 5/16 inch straight cylindrical shank, a 13/16 inch length of cut, and a 2-1/2 inch overall length. The 30-degree spiral flute geometry and right-hand cut with right-hand flute direction promote efficient chip evacuation and stable cutting action. Its centercutting capability allows plunge entry directly into the workpiece. Machining centers and CNC mills in job shops, tool rooms, and production environments are the primary setting for this tool.

This end mill is suited for slotting, profiling, and peripheral milling in ferrous and non-ferrous materials where a regular-length, uncoated carbide tool is appropriate. The uncoated finish and C2 carbide grade make it a practical choice for aluminum, brass, plastics, and softer steels where a coating is unnecessary or where re-sharpening is anticipated. It ships as a single unit and is a direct fit wherever a 5/16 inch shank, 2-flute square end mill of regular length is specified.

Key Features

• Solid carbide construction, C2 material grade, for rigidity and wear resistance
• 2 flutes with 30-degree spiral geometry for efficient chip removal
• Centercutting design allows direct plunge milling without a pre-drilled hole
• Right-hand cut and right-hand flute direction for standard CNC and manual mill setups
• Uncoated finish suitable for non-ferrous metals, plastics, and softer alloys
• Regular-length geometry with straight cylindrical shank for broad collet and chuck compatibility

Compatibility

Designed as an OEM-style replacement or standard tooling option for any machine spindle accepting a 5/16 inch straight cylindrical shank end mill, including ER collet systems and end mill holders sized for 5/16 inch tooling.

Installation Notes

Installation is performed by a machinist or CNC operator. Ensure the spindle and collet or tool holder are clean and free of debris before seating the shank. Confirm runout with a dial indicator after tightening to the tool holder manufacturer's specified torque. Always power down and lock out the machine before changing tooling per applicable shop safety and OSHA lockout/tagout procedures.