Hertel 04138434 Cobalt Jobber Drill Bit 7/16 Inch

Product Description

The HERTEL 04138434 is a cobalt jobber-length drill bit designed for heavy-duty holemaking in demanding materials. It features a 135-degree split point that reduces walking and requires less feed pressure at the start of the cut. The oxide and TiN coating helps resist heat and extends tool life in high-friction applications. At 5.5 inches overall length with a 4.0625-inch flute, it fits standard drill chucks and CNC setups alike. Machinists, millwrights, and maintenance technicians reach for cobalt-grade bits when drilling hardened steel, stainless, cast iron, or other tough alloys where standard HSS bits wear prematurely.

This bit is suited for production and maintenance environments where materials push past the limits of standard high-speed steel tooling. The right-hand spiral flute with web-thinned, tapered web geometry evacuates chips cleanly in deep-hole applications. The straight cylindrical shank diameter of 7/16 inch seats in standard three-jaw chucks and collet holders without modification. It is a single-piece consumable typically purchased per-bit for tool cribs, job boxes, or machine shop inventory.

Key Features

• Cobalt steel construction rated for heavy-duty holemaking in hard and abrasive materials
• 135-degree split point reduces thrust and minimizes drill walk on entry
• Oxide and TiN dual coating improves heat resistance and extends tool life
• Web-thinned, tapered web geometry improves chip evacuation in deeper holes
• Regular right-hand spiral flute compatible with standard drill press and CNC spindles
• Straight cylindrical shank fits standard 3-jaw chucks and collet systems without adaptation

Compatibility

Designed as a jobber-series replacement drill bit for use in any standard drill press, CNC machining center, or hand-held power drill equipped to accept a 7/16-inch straight cylindrical shank. Suitable for holemaking operations within the 0.4000 to 0.5000 decimal inch drill size range.

Installation Notes

A licensed machinist or qualified maintenance technician should secure the shank fully in the chuck or collet before operation and verify runout before cutting. Always power down and lock out the machine spindle before changing bits. Cutting speeds and feeds should be set per the workpiece material; cobalt bits tolerate higher heat than HSS but still benefit from proper cutting fluid in ferrous materials. Do not use this bit for coolant-through applications as the design does not support internal coolant delivery.