Osg 402-1378 Square End Mill 0.1378 in 2 Flute Carbide

Product Description

The OSG 402-1378 is a solid carbide square end mill designed for precision milling operations in metalworking and machining applications. With a 0.1378 inch (3.50 mm) cutting diameter and a 0.4724 inch (12.00 mm) length of cut, this tool handles slotting, profiling, and pocketing in a variety of ferrous and non-ferrous materials. The two-flute geometry and 30-degree helix angle promote efficient chip evacuation and reduce cutting resistance at smaller diameters. Manufactured from micrograin solid carbide, it delivers the rigidity and edge retention required for consistent, repeatable cuts in production and job-shop environments. The uncoated finish makes it straightforward to inspect for wear.

This end mill is suited for CNC machining centers and manual mills where small-diameter, high-precision work is required. The centercutting design allows direct plunge entry into the workpiece, expanding its utility for ramping, plunging, and full-slot operations. Right-hand cut and right-hand flute orientation is standard for conventional spindle setups. Its regular-length profile fits standard toolholders used in light to medium-duty milling of aluminum, brass, steel, and similar materials common in tool-and-die, aerospace component, and general precision machining work.

Key Features

• 0.1378 inch (3.50 mm) cutting diameter with 0.4724 inch (12.00 mm) length of cut
• Micrograin solid carbide construction for superior edge retention and rigidity
• 2-flute, 30-degree spiral helix for efficient chip evacuation at small diameters
• Centercutting geometry enables plunge, ramp, and full-slot entry
• Right-hand cut, right-hand flute — compatible with standard CNC spindle rotation
• Uncoated finish; no coating masking of edge geometry

Compatibility

Designed as an OEM-style replacement or direct-use solid carbide end mill in the OSG Series 402 line, fitting standard toolholders accepting a 4.00 mm (approximately 0.1575 inch) shank diameter in CNC machining centers and manual milling machines.

Installation Notes

Installation should be performed by a qualified machinist or CNC setup technician. Ensure the spindle is fully stopped and the machine is powered down before changing tooling. Seat the shank fully and evenly in the collet or toolholder, and torque the retention mechanism per the toolholder manufacturer specifications. Verify runout with a dial indicator before beginning a production cut, as runout is especially critical at small diameters to prevent premature tool breakage.