Accupro 319921 Ball End Mill 1/4 in 3 Flute Solid Carbide

Product Description

The ACCUPRO 319921 is a single-end ball end mill designed for precision profiling, contouring, and 3D milling operations in a wide range of materials. Built from micrograin solid carbide, it offers the rigidity and edge retention needed for demanding cutting applications. The 1/4 inch cutting diameter pairs with a 3/8 inch length of cut and a 4 inch overall length, giving it the reach necessary for detailed work in deeper cavities. A 37-degree right-hand spiral helix promotes efficient chip evacuation and reduces cutting forces. The ZrN (zirconium nitride) coating adds surface hardness and heat resistance, extending tool life in both ferrous and non-ferrous materials. This tool is installed and operated by machinists and CNC tooling specialists.

This end mill is suited for CNC milling centers and manual knee mills requiring a 1/4 inch shank. The 2-1/8 inch reach length makes it practical for profiling pockets, contoured surfaces, and complex 3D geometry where a shorter tool would not clear the workpiece. It is appropriate for use in aluminum, steel, stainless steel, and similar materials where a ZrN-coated carbide tool is specified. The single-end configuration is standard for toolholders requiring a straight shank. Right-hand cutting direction is compatible with conventional CNC spindle rotation.

Key Features

• Micrograin solid carbide construction for superior edge retention and rigidity
• ZrN coating increases surface hardness and extends tool life in ferrous and non-ferrous applications
• 37-degree right-hand spiral helix promotes chip evacuation and reduces heat buildup
• 3 flutes balance chip clearance and cutting edge count for smooth finishes
• 2-1/8 inch reach length allows access to deeper pockets without interference
• Tight shank diameter tolerance (+0.0001/-0.0004 inches) ensures consistent toolholder fit

Compatibility

Designed as a direct-fit replacement for 1/4 inch shank ball end mill applications on CNC machining centers and manual mills accepting a 1/4 inch straight shank toolholder.

Installation Notes

Installation is performed by a qualified machinist or CNC setup technician. Ensure the spindle is fully stopped and the machine is in a safe, locked-out state before changing tooling. Seat the shank fully into the toolholder and tighten to the holder manufacturer's specified procedure. Verify runout with a dial indicator before beginning any cut to confirm proper seating and avoid premature tool wear or breakage.