Hertel 79891958 Solid Carbide Jobber Drill Bit No. 42

Product Description

The HERTEL 79891958 is a solid carbide jobber-length drill bit sized to wire gauge No. 42, with a decimal diameter of 0.0935 inches. It features a 118-degree standard point angle, a bright (uncoated) finish, and a right-hand spiral flute configuration. Overall length is 2 inches with a 1-inch flute length. Solid carbide construction at material grade C2 delivers the rigidity and wear resistance needed for precision small-diameter drilling in hard or abrasive materials. The web-thinned, tapered web design reduces thrust and improves chip evacuation in production or maintenance drilling applications.

This bit is suited for metalworking, tool-and-die, and maintenance operations where a small-diameter, high-precision hole is required. The straight-cylindrical shank accepts standard drill chucks and collet holders. Its 0.0935-inch diameter and jobber length make it a common choice for tapping pilot holes, instrument assembly, and precision part fabrication in shop or field environments. Machinists, toolmakers, and maintenance technicians working with steel, cast iron, and similar materials will find this bit appropriate for moderate to high-volume drilling cycles.

Key Features

• Solid carbide construction, material grade C2, for hardness and wear resistance
• 118-degree standard point angle with web-thinned, tapered web for reduced thrust
• Bright finish — no coating interference on tight-tolerance holes
• Right-hand cut, regular spiral flute with 2 flutes for efficient chip removal
• Diameter tolerance of -0.0005 to 0.0000 inches for consistent, repeatable hole size
• Straight-cylindrical shank compatible with standard drill chucks and collet holders

Compatibility

Designed for use in standard drill chucks and collet systems that accept a 0.0935-inch straight-cylindrical shank. Fits within the 0.0500 to 0.1000 inch drill bit size range category. No coolant-through capability; intended for dry or externally lubricated drilling setups.

Installation Notes

Installation and use should be performed by qualified machinists or maintenance technicians familiar with small-diameter carbide tooling. Carbide is brittle — avoid side loading, interrupted cuts, or excessive feed rates that can cause tip fracture. Secure the shank fully in the chuck or collet and verify runout before drilling. Follow machine manufacturer guidelines and applicable shop safety standards when operating drilling equipment.