Iscar 3398004 Corner Radius End Mill 1/4 in 4 Flute Carbide

Product Description

The ISCAR 3398004 is a solid carbide corner radius end mill from the ECI-4-VF series, designed for high-performance milling in demanding material applications. It features a 1/4 inch diameter, a 0.015 inch corner radius, and four flutes with a variable index geometry that supports both roughing and finishing passes in a single tool. The AlTiCrSiN PVD coating provides thermal resistance and surface hardness suited to cutting steel, stainless steel, cast iron, superalloys, titanium, and hard materials. Centercutting capability allows plunge entry without a pre-drilled pilot hole. This tool is installed by machinists and CNC tooling technicians working in precision manufacturing environments.

The 3398004 is built for shops running steel, stainless, cast iron, superalloys, titanium, and hard material workpieces where tool life and finish quality matter. With a short length type, 3/8 inch length of cut, and a straight-cylindrical shank with h6 tolerance, it seats securely in standard collet or milling toolholders. Extended reach geometry adds clearance in deeper pockets without sacrificing rigidity. The right-hand flute direction and right-hand cutting direction suit conventional CNC vertical and horizontal machining center setups.

Key Features

• Solid carbide submicron-grade construction for rigidity and edge retention in hard materials
• AlTiCrSiN PVD coating rated for steel, stainless steel, cast iron, superalloys, titanium, and hard materials
• Variable index flute spacing reduces harmonic chatter during aggressive cuts
• 0.015 inch corner radius blends radii and reduces stress concentrations at shoulder transitions
• Centercutting design permits direct plunge milling without a pre-drilled hole
• Extended reach with short length type balances access depth and tool stiffness
• Right-hand spiral flutes with normal pitch for consistent chip evacuation

Compatibility

Designed for use with standard collet chucks and milling toolholders accepting a 1/4 inch straight-cylindrical shank with h6 tolerance. The manufacturers catalog number for this tool is ECI-4 250-375C015VF2. Compatible with CNC machining centers and manual mills configured for right-hand cutting tools.

Installation Notes

Installation is performed by a qualified machinist or CNC tooling technician. Power down and lock out the spindle before inserting or removing the tool from the toolholder. Ensure the collet or chuck bore is clean and free of chips before seating the shank, and torque the retention nut to the toolholder manufacturers specification. Verify runout at the tool tip with a dial indicator before beginning a production run, as submicron carbide is sensitive to seating inconsistencies.