Hertel C.E03.0249 Aircraft Extension Drill Bit No. 40

Product Description

The HERTEL C.E03.0249 is a No. 40 wire-size aircraft extension drill bit engineered for drilling in tight or hard-to-reach spaces where standard-length bits cannot reach. Built from high-speed steel with an oxide finish, it measures 6 inches overall length with a 1.375-inch spiral flute and a 0.0980-inch diameter. The 135-degree split point is self-centering and web-thinned, reducing the force needed to start a hole and minimizing walking on entry. This bit is a general-purpose cutting tool suited for use by aircraft maintenance technicians, machinists, and metalworkers requiring extended reach in structural or assembly drilling applications.

This drill bit is designed for use in aircraft maintenance, sheet metal fabrication, and structural assembly work where access depth is limited by conventional bit lengths. The extended 6-inch overall length allows drilling through deep channels, tight bays, and stacked material assemblies. Its right-hand spiral flute design provides efficient chip evacuation during through-hole drilling in ferrous and non-ferrous metals. It conforms to NAS 907 standards, making it appropriate for aerospace and precision metalworking environments.

Key Features

• No. 40 wire size (0.0980 inches diameter) with matching straight-cylindrical shank for standard chuck compatibility
• 135-degree split point is self-centering and reduces drill walking on entry
• Web-thinned, tapered web construction reduces thrust and cutting resistance
• 6-inch overall length provides extended reach for aircraft and structural applications
• High-speed steel construction with oxide finish for general-purpose metal drilling
• Conforms to NAS 907 standard for aerospace drill bit performance

Compatibility

Designed as a general-purpose aircraft extension drill bit compatible with standard straight-shank drill chucks accepting a 0.0980-inch diameter shank, suitable for aerospace, sheet metal, and structural metal drilling applications.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists, aircraft maintenance technicians, or sheet metal workers. Ensure the workpiece is properly secured and the drill chuck is tightened fully before operation. Confirm spindle speed is appropriate for the material and bit diameter before beginning the cut. Inspect the bit for wear or damage before each use and replace if the cutting edges show signs of dulling or chipping.