Robbjack C8-303-08 Square End Mill 1/4 in 3 Flute Carbide

Product Description

The ROBBJACK C8-303-08 is a solid carbide square end mill designed for precision material removal in milling operations. Built to Series C8-305 specifications, it features a 0.25 inch cutting diameter, a 0.75 inch length of cut, and a 2.5 inch overall length with a 0.25 inch straight-cylindrical shank. The three-flute geometry and 30-degree helix angle promote efficient chip evacuation and smooth cutting action. Uncoated and center-cutting, this end mill is suited for both plunge and peripheral milling. It is installed and operated by machinists and CNC operators working in job shops, tool rooms, and production environments.

This end mill is appropriate for general-purpose milling applications where a regular-length, three-flute carbide tool is required. The right-hand cut and right-hand spiral flute configuration is standard for conventional CNC machining centers and manual knee mills. The uncoated solid carbide construction makes it well suited for non-ferrous metals, plastics, and other materials where coatings are not required or where re-sharpening is anticipated. The C8-305 series designates a regular-length geometry, keeping deflection low in standard-depth applications.

Key Features

• 0.25 inch cutting diameter with a mill diameter tolerance of +0.000 / -0.002 inches for consistent dimensional accuracy
• Three flutes with a 30-degree helix angle for balanced chip flow and surface finish
• Center-cutting design allows direct plunge entry without a pre-drilled pilot hole
• Solid carbide construction in material grade C2 for rigidity and wear resistance
• Right-hand cut, right-hand flute, spiral flute geometry - standard configuration for most CNC setups
• Straight-cylindrical shank with a shank diameter tolerance of -0.0001 / -0.0002 inches for secure collet or end mill holder retention

Compatibility

Designed as an OEM-style replacement or direct-use solid carbide square end mill within the ROBBJACK C8-305 series, suitable for standard 1/4 inch collets, ER collet chucks, and end mill holders on CNC machining centers and manual milling machines.

Installation Notes

Installation should be performed by a qualified machinist or CNC operator. Ensure the machine spindle is fully powered down and at a complete stop before inserting or removing the end mill from its holder. Verify collet or holder bore size matches the 0.25 inch shank diameter before clamping, and torque the retention nut per the toolholder manufacturer specifications. Inspect the cutting edges for chips or damage before each use.