Hertel 74460031 Solid Carbide Jobber Drill Bit 8 Mm

Product Description

The HERTEL 74460031 is a solid carbide jobber-length drill bit designed for precision hole-making in demanding materials. Sized at 8 mm (0.3150 inches) in diameter, it features a 118-degree standard drill point angle and a two-flute regular spiral configuration for efficient chip evacuation. The bright finish is left uncoated for straightforward regrinding when needed. With an overall length of 3.75 inches and a flute length of 2.375 inches, this bit fits standard drill chucks via its straight cylindrical shank. It is intended for use by machinists and tool-and-die professionals working on CNC machines, manual mills, or drill presses requiring tight-tolerance bores.

This jobber drill bit is rated for general-purpose drilling applications across a range of metals and engineered materials. Its web-thinned, tapered web construction reduces entry force and improves centering at the cut. The carbide grade C2 substrate provides the hardness and rigidity required when drilling cast iron, aluminum alloys, plastics, and similar materials at higher spindle speeds than high-speed steel alternatives allow. It suits production and job-shop environments where consistent hole diameter tolerance is critical.

Key Features

• Solid carbide construction, C2 material grade, for high rigidity and wear resistance
• 118-degree standard point angle with web thinning for reduced thrust force
• Tapered web configuration improves self-centering on entry
• Bright (uncoated) finish allows easy visual inspection and regrinding
• Right-hand cut, regular spiral flute for reliable chip clearing
• Straight cylindrical shank fits standard drill chucks without adapters
• Diameter tolerance of -0.0005 to 0.0000 inches for close-tolerance hole requirements

Compatibility

Designed as a general-purpose replacement or production drill bit for applications requiring an 8 mm (0.3150-inch) diameter hole, fitting within the 0.3000 to 0.3500 inch drill bit size range for standard three-jaw and collet-style drill chucks.

Installation Notes

Installation should be performed by a qualified machinist following the machine tool manufacturer guidelines for chuck torque and runout. Ensure the spindle and workpiece are fully secured before engaging the cut. Carbide is brittle compared to high-speed steel - avoid side loading or interrupted cuts that exceed the bit's lateral strength. Always match spindle speed and feed rate to the workpiece material; consult published carbide drilling speed-and-feed charts for the specific material being machined.