Harvey Tool 20157-C3 Micro Drill Bit 0.4 Mm Solid Carbide

Product Description

The HARVEY TOOL 20157-C3 is a solid carbide micro drill bit designed for precision drilling in demanding materials at extremely small diameters. Built for the miniature drilling series, this bit features a 130-degree point angle optimized for accurate entry and reduced walking on hard substrates. The AlTiN (aluminum titanium nitride) coating provides elevated heat resistance and extended tool life in high-speed applications. With a 0.0157-inch (0.4 mm) cutting diameter and a 1/8-inch shank, it fits standard collet systems used in CNC machining centers and manual drill presses. Machinists, toolmakers, and precision fabricators rely on this geometry for micro-hole work in ferrous and non-ferrous alloys.

This bit is suited for precision machining applications where tight-tolerance, small-diameter holes are required. Typical use cases include printed circuit board (PCB) drilling, watch and instrument component fabrication, medical device manufacturing, and aerospace detail work. The right-hand spiral flute promotes efficient chip evacuation in blind and through-hole configurations. The 0.27-inch flute length and 1.5-inch overall length keep the bit rigid, minimizing deflection at this diameter scale.

Key Features

• Solid carbide construction for rigidity and wear resistance at micro diameters
• AlTiN coating for heat resistance and extended tool life in hard materials
• 130-degree point angle reduces drill walking and improves entry accuracy
• Right-hand spiral flute promotes chip clearing in both blind and through holes
• 1/8-inch shank diameter compatible with standard collet and chuck systems
• 0.27-inch flute length with 1.5-inch overall length for maximum rigidity at this scale

Compatibility

Designed as an OEM-style miniature drill bit compatible with standard 1/8-inch collet systems and precision drill chucks used in CNC machining centers, drill presses, and high-speed spindles.

Installation Notes

Installation and use should be performed by qualified machinists familiar with micro-tooling practices. Ensure the collet or chuck is clean and properly torqued before use, and verify spindle runout is within acceptable limits, as even minor runout can cause tool breakage at this diameter. Reduce feed rates and use appropriate cutting fluid or air blast for chip evacuation. Never force the bit into a non-rotating chuck or exceed the recommended spindle speed range for the work material.