Hertel C.E07.0485 Aircraft Extension Drill Bit No. 11

Product Description

The HERTEL C.E07.0485 is a cobalt aircraft extension drill bit designed for drilling in tight spaces and hard-to-reach locations where standard-length bits cannot reach. Built from cobalt high-speed steel with a straw finish, this bit handles high-heat applications and harder materials without losing its edge. It carries a No. 11 wire gauge size with a decimal equivalent of 0.1910 inches, a 135-degree split point for self-centering entry, and a 12-inch overall length that provides the reach required in aerospace and structural fabrication work. The web-thinned, tapered web configuration reduces thrust and improves chip evacuation during deep drilling operations.

This extension drill bit is suited for aircraft assembly, sheet metal work, structural steel fabrication, and any application where deep reach or clearance past obstructions is required. The 135-degree split point eliminates the need for a center punch on most materials, and the right-hand spiral flute promotes efficient chip removal. It meets NAS 907 standards, making it appropriate for aerospace and defense maintenance work as well as general industrial applications where dimensional precision is critical.

Key Features

• Cobalt construction provides heat and wear resistance for drilling harder materials
• 135-degree split point is self-centering, reducing walking and eliminating center-punch steps
• 12-inch overall length delivers extended reach for confined or obstructed work areas
• Straw finish indicates cobalt content and helps dissipate heat during high-speed drilling
• Web-thinned tapered web reduces drilling thrust and improves chip flow
• Meets NAS 907 standard for aerospace and structural applications

Compatibility

Designed as a general-purpose aircraft extension drill bit for use in standard straight-cylindrical shank chucks; suitable for hand drills, drill presses, and right-angle drill motors used in aerospace, sheet metal, and structural fabrication applications.

Installation Notes

This bit is installed and removed by a licensed machinist, aircraft mechanic, or qualified fabricator using a compatible drill chuck sized for a 0.1910-inch straight-cylindrical shank. Secure the workpiece firmly before drilling and verify chuck tightness to prevent bit slippage at extended reach. Allow the bit to cool between deep drilling passes to preserve cobalt cutting edges, and avoid forcing the bit at reduced RPM in very hard stock without appropriate cutting fluid.