Robbjack STR-404-09-A Square End Mill 9/32 in 4 Flute Carbide

Product Description

The ROBBJACK STR-404-09-A is a solid carbide square end mill designed for precision milling in ferrous and non-ferrous metal applications. It features a 9/32-inch cutting diameter, a 3/4-inch length of cut, and a 5/16-inch shank diameter, with an overall length of 2-1/2 inches. The four-flute, fine-pitch geometry paired with an AlTiN coating provides heat resistance and extended tool life in high-speed cutting operations. The 30-degree helix angle promotes efficient chip evacuation and smooth cutting action. This tool is installed and used by machinists and CNC operators in production and job-shop environments.

The STR-404-09-A is suited for slotting, peripheral milling, and profiling operations in materials where heat generation at the cutting edge is a concern. Its centercutting capability allows it to plunge directly into the workpiece. The regular-length geometry fits standard toolholders and is well-matched to vertical machining centers and manual mills requiring a compact, rigid end mill in the 9/32-inch diameter range.

Key Features

• 9/32-inch cutting diameter with 3/4-inch length of cut for controlled depth engagement
• Solid carbide construction for rigidity and dimensional stability under load
• AlTiN finish increases surface hardness and thermal resistance at the cutting edge
• 4-flute, fine-pitch design improves surface finish and feed rate capability
• 30-degree helix angle promotes efficient chip flow and reduces cutting forces
• Centercutting geometry allows direct plunge entry without pre-drilling
• Right-hand cut and right-hand flute configuration for standard spindle rotation

Compatibility

Designed as an OEM-style replacement and standard production end mill within the ROBBJACK STR-404 series, compatible with 5/16-inch collets, end mill holders, and toolholders accepting a 5/16-inch shank diameter.

Installation Notes

Installation should be performed by a qualified machinist or CNC operator following the machine tool builder guidelines for toolholder tightening and runout verification. Ensure the spindle is fully stopped and the machine is in a safe state before changing tooling. Confirm collet or toolholder condition before seating the shank to avoid runout that can reduce tool life. Follow the cutting tool manufacturer recommended speeds and feeds for the workpiece material and do not exceed the rated depth of cut for this tool diameter.