Promax 139-01624 Corner Rounding End Mill 1/4 in 4 Flute

Product Description

The PROMAX 139-01624 is a double-end corner rounding end mill designed for precision edge-breaking and radius profiling on metal and hard materials. Built from micrograin solid carbide and coated with AlTiN (aluminum titanium nitride), it delivers extended tool life in high-heat cutting applications. The 4-flute geometry supports efficient chip evacuation while maintaining surface finish quality. With a 0.05 mm corner radius and a 1/4 inch mill diameter, it produces consistent, repeatable radiused edges on ferrous and non-ferrous workpieces. Machinists and toolroom operators working in CNC milling environments rely on this geometry for finishing passes where edge quality is critical.

This end mill is suited for use on CNC machining centers and manual knee mills handling steel, stainless, aluminum, and similar materials where a controlled corner radius is required. The double-end configuration extends tool service life by providing two usable cutting ends. Right-hand cut and right-hand flute direction make it compatible with standard spindle rotation. The Series 139 designation places it within PROMAX's corner rounding line, appropriate for production and toolroom environments requiring tight radius tolerances.

Key Features

• Micrograin solid carbide construction for rigidity and wear resistance in demanding cuts
• AlTiN coating improves heat resistance and tool life in ferrous and high-temp alloy applications
• Double-end design provides two cutting ends, extending usable tool life
• 0.05 mm corner radius with a radius tolerance of 0.001 inch for precise edge forming
• 4-flute, right-hand cut and flute configuration for standard CNC spindle compatibility
• 0.145 inch tip diameter suits fine-detail profiling and finishing passes

Compatibility

Designed for use in standard 1/4 inch collets and tool holders on CNC machining centers and manual milling machines requiring a corner rounding end mill with right-hand cut geometry.

Installation Notes

Installation should be performed by a qualified machinist following shop safety protocols. Ensure the spindle is fully stopped and the machine is powered down before changing tooling. Seat the 1/4 inch shank fully into a clean, properly sized collet or tool holder and torque to the holder manufacturer's specification. Verify runout with a dial indicator before beginning a cutting pass to protect both the tool and the workpiece.