Hertel C.E07.0237 Aircraft Extension Drill Bit 42 Cobalt

Product Description

The HERTEL C.E07.0237 is a cobalt aircraft extension drill bit engineered for precision drilling in aircraft structural and maintenance applications. Built to a 12-inch overall length, this bit provides the reach required when working in recessed airframe cavities where standard-length bits fall short. The 135-degree split point is self-centering and reduces the need for a center-punch start, which matters when working on sheet metal or composite assemblies. The straw finish cobalt construction handles elevated heat at the cutting zone without sacrificing edge life. Licensed HVAC, avionics, and airframe technicians as well as aerospace MRO shops rely on this configuration for repeatable, clean-hole production.

This bit is intended for drilling aluminum, stainless steel, titanium, and other materials common to aircraft construction and repair. The 12-inch extended reach suits applications where access is limited, such as drilling through structural ribs, bulkheads, or multi-layer stack-ups that cannot be easily repositioned. The right-hand spiral flute evacuates chips effectively, reducing the risk of chip packing in deep-reach drilling situations. The bit conforms to NAS 907 standards, making it appropriate for aerospace OEM and MRO environments where dimensional and performance certification is required.

Key Features

• Cobalt tool material with straw finish for heat resistance and extended tool life in tough alloys
• 135-degree split point is self-centering, eliminating the need for a center punch on most materials
• 12-inch overall length provides extended reach for drilling in confined airframe locations
• Right-hand spiral flute with tapered web and web-thinned geometry for efficient chip evacuation
• Straight cylindrical shank compatible with standard drill chucks
• Meets NAS 907 standard for aerospace-grade dimensional and performance compliance

Compatibility

Designed as an extended-reach replacement or supplemental drill bit for aerospace MRO, aircraft assembly, and structural repair operations requiring a wire-size 42 cobalt bit conforming to NAS 907.

Installation Notes

This bit is installed and operated by airframe technicians, aerospace MRO professionals, and machinists working under applicable FAA, OEM, or depot maintenance procedures. Secure the straight cylindrical shank firmly in a calibrated drill chuck before use and verify chuck runout is within acceptable limits to preserve hole tolerance. Reduce feed pressure when breaking through the far side of stack-ups to prevent burr formation and bit deflection. Do not exceed the material and speed recommendations appropriate for cobalt tooling in the specific alloy being drilled.