Hertel 42171 Screw Machine Drill Bit 3/64 in Cobalt

Product Description

The HERTEL 42171 is a screw machine length drill bit designed for high-performance drilling in tough workpiece materials. Built from M35 cobalt steel with an oxide straw coating, this bit handles hardened materials, heat-treatable alloy steels, stainless steel, and titanium alloy where standard HSS bits fail. The 135-degree split point reduces walking and lowers thrust required at entry, making it well suited for production drilling and repetitive operations. At 1-3/8 inches overall length with a 1/2-inch flute length, the stub-length body provides rigidity and minimizes deflection in short-reach applications. The 3/64-inch (0.0469 inch) diameter is intended for precision small-hole work across machining and fabrication environments.

Screw machine length drill bits are the standard choice for CNC machining centers, drill presses, and hand-held power tools where rigidity matters more than reach. The HERTEL 42171 fits production shop, MRO, and field-service applications where operators are drilling stainless steel fastener holes, hard alloy components, or titanium fittings. The short flute-to-diameter ratio of 3xD keeps the bit stable under load. Machinists, tool-and-die technicians, and mechanical contractors performing precision metalwork are the primary users of this bit size and geometry.

Key Features

• M35 cobalt steel construction resists heat buildup when drilling stainless steel and titanium alloy
• Oxide straw coating reduces friction and extends cutting edge life
• 135-degree split point minimizes bit walk and reduces entry thrust
• Stub screw machine length (1-3/8 inches OAL) provides maximum rigidity and reduces deflection
• Regular spiral with spiral flutes for efficient chip evacuation in short-hole drilling
• No coolant-through requirement simplifies setup on standard drill press and handheld equipment

Compatibility

Designed as an OEM-style screw machine length drill bit suitable for standard drill chucks and collet systems accepting a 3/64-inch shank in CNC machining centers, drill presses, and power hand tools.

Installation Notes

Installation and use of this drill bit should be performed by machinists or qualified trade professionals familiar with metalworking equipment. Ensure the drill chuck or collet is fully secured and the workpiece is clamped before operation. When drilling hardened materials or stainless steel, use appropriate cutting fluid to manage heat even though the bit does not require coolant-through delivery. Inspect the cutting edge before each use and replace the bit if chipping or dulling is observed to prevent workpiece damage or bit breakage.