Hertel C.E07.1111 Aircraft Extension Drill Bit 7/16 in Cobalt

Product Description

The HERTEL C.E07.1111 is a cobalt aircraft extension drill bit designed for drilling through hard metals, stainless steel, and high-alloy materials in aerospace and industrial applications. It measures 7/16 inch (0.4375 inch) in diameter with a 12-inch overall length, giving technicians the extended reach needed to access deep or confined bore locations. The 135-degree split point is self-centering and reduces walking on contact, eliminating the need for a center punch on most surfaces. A straw finish indicates the cobalt content has been heat-treated for added hardness and wear resistance. Machinists and aircraft maintenance technicians are the primary installers of this bit.

This extension drill bit is suited for production and MRO environments where standard-length bits cannot reach the work surface. The extended shank is especially useful in aircraft fuselage, wing assembly, and structural repair work where fastener holes must be drilled through layered or recessed material. It is also applied in general industrial fabrication when working inside deep housings, frames, or channels. The spiral flute design efficiently clears chips even during extended reach drilling operations.

Key Features

• Cobalt tool material for high heat resistance and durability in hard-metal drilling
• 135-degree split point is self-centering, reducing drill walking on hard or curved surfaces
• 12-inch overall length provides extended reach for confined or deep-access applications
• 4.0625-inch spiral flute length promotes efficient chip evacuation during drilling
• Web-thinned tapered web reduces thrust force and improves cutting efficiency
• Straight cylindrical shank fits standard drill chucks without adapters
• Meets NAS 907 standard for aircraft extension drill bits

Compatibility

Designed as an OEM-style aircraft extension drill bit compatible with standard straight-shank drill chucks accepting a 7/16-inch shank diameter.

Installation Notes

This bit is installed and operated by machinists, aircraft maintenance technicians, and industrial drill press or handheld drill operators. Secure the straight cylindrical shank firmly in the chuck before use and verify runout is within acceptable limits for the application. Use appropriate cutting fluid or coolant when drilling hard alloys to extend bit life and manage heat buildup. Follow applicable workplace safety standards and, for aircraft structural work, adhere to relevant aviation maintenance regulations governing hole size tolerances and fastener fit.