Hertel C.E07.0373 Aircraft Extension Drill Bit No. 26

Product Description

The HERTEL C.E07.0373 is a cobalt aircraft extension drill bit engineered for demanding drilling applications where standard-length bits cannot reach. Built to NAS 907 standards, it carries a No. 26 wire gauge size (0.1470 inches decimal) and a 135-degree split point that self-centers on contact, reducing walk and the need for a center punch. The straw finish helps resist heat buildup during extended drilling cycles. At 12 inches overall length, this bit gives technicians and machinists the reach needed for airframe structures, deep cavities, and confined assembly areas. A straight cylindrical shank fits standard chucks without adapters.

This bit is suited for aerospace fabrication, sheet metal work, and structural drilling tasks where access depth is a limiting factor. The cobalt construction handles harder alloys and stainless steels better than standard high-speed steel. Right-hand spiral flutes evacuate chips efficiently, keeping the cutting edge clear during through-hole and blind-hole operations. General-purpose performance rating makes it appropriate across a range of metal substrates encountered in production and MRO environments. It is commonly installed by aircraft maintenance technicians, aerospace fabricators, and precision machinists.

Key Features

• No. 26 wire gauge size, 0.1470 inches decimal diameter
• 135-degree split point with self-centering geometry reduces walk and eliminates center-punch requirement
• Cobalt tool material withstands elevated cutting temperatures and harder alloys
• 12-inch overall length provides extended reach for deep or confined drilling locations
• Straw finish aids heat resistance during high-cycle or continuous drilling operations
• Web-thinned, tapered web configuration reduces thrust and improves chip flow
• Meets NAS 907 standard for aircraft extension drill bits

Compatibility

Designed as a general-purpose aircraft extension drill bit compatible with standard straight-shank drill chucks accepting a 0.1470-inch diameter shank, suitable for use in hand drills, drill presses, and pneumatic drilling equipment common in aerospace and metal fabrication environments.

Installation Notes

Installation and use should be performed by qualified machinists, aircraft maintenance technicians, or metalworkers familiar with proper drilling technique for cobalt tooling. Secure the workpiece fully before drilling to prevent movement and bit breakage. Use appropriate cutting fluid or lubrication when drilling hard alloys to extend bit life and maintain dimensional accuracy. Inspect the cutting edge for wear or chipping before each use, as cobalt bits are more brittle than standard high-speed steel and can fracture under side-loading or excessive feed pressure.