Robbjack SR-2-040 Square End Mill 0.04 in 2 Flute Carbide

Product Description

The ROBBJACK SR-2-040 is a miniature solid carbide square end mill from the SR-2 series, designed for precision milling of small features in metalworking, toolroom, and production machining applications. The cutting diameter measures 0.04 inches with a 0.12-inch length of cut, a 1/8-inch straight-cylindrical shank, and a 1.5-inch overall length. Built from solid carbide in ROBBJACK's Tuffy material grade, this two-flute tool delivers the rigidity and edge retention required when holding tight dimensional tolerances on small-part work. It ships uncoated and is suited for machinists and toolmakers running CNC mills or manual equipment where fine detail cutting is the priority.

This end mill is used in precision machining environments including mold and die work, medical device manufacturing, aerospace component work, and general toolroom applications where small-diameter features such as slots, pockets, and contours must be cut accurately. The 0.04-inch diameter makes it appropriate for micro-milling operations where larger tools cannot access the geometry. Its regular-length configuration fits standard tool holders without extended-reach considerations, keeping deflection minimal at this diameter.

Key Features

• 0.04-inch cutting diameter with a tight mill diameter tolerance of plus 0.0005 / minus 0.0005 inches
• Solid carbide construction in Tuffy material grade for hardness and wear resistance
• Two-flute, spiral-flute geometry with a 30-degree helix angle for chip evacuation in small cavities
• Centercutting design allows plunge entry directly into the workpiece
• Right-hand cut and right-hand flute orientation - standard configuration for conventional CNC spindle rotation
• 1/8-inch straight-cylindrical shank with a shank diameter tolerance of minus 0.0001 / minus 0.0002 inches for consistent tool holding

Compatibility

Designed as an OEM-style replacement and standard production tool in the ROBBJACK SR-2 series; fits any tool holder or collet accepting a 1/8-inch straight-cylindrical shank.

Installation Notes

Installation is performed by qualified machinists or toolroom technicians. Ensure the spindle is fully powered down and the machine is in a safe state before loading or changing any end mill. Use a calibrated collet or end mill holder sized for a 1/8-inch shank and verify runout with a dial indicator before beginning a cut, as runout has a disproportionate effect on tool life and surface finish at this diameter. Do not exceed the 0.12-inch length of cut; engaging flute length beyond this value risks tool deflection or breakage on a tool of this size.