Hertel C.E07.0226 Aircraft Drill Bit No. 43 Cobalt

Product Description

The HERTEL C.E07.0226 is a cobalt aircraft extension drill bit designed for deep-reach drilling in tight clearance applications where a standard-length bit cannot access the worksite. Built to a wire gauge size of No. 43 with a decimal diameter of 0.0890 inches, this bit features a 135-degree split point that promotes self-centering on entry and reduces walking without a center punch. The straw finish is characteristic of cobalt high-speed steel tooling, providing moderate heat resistance during high-feed drilling into steel, stainless, and other hard alloys. With a 12-inch overall length and a 1.25-inch spiral flute, this bit is suited for production drilling, aerospace maintenance, and structural fabrication environments.

Aircraft extension drill bits in this size range are used in aerospace assembly, sheet metal work, aircraft repair stations, and structural steel fabrication where access depth is a constraint. The No. 43 wire gauge size is common in applications requiring close-tolerance holes for fasteners, rivets, or pilot passes. Right-hand cutting direction and a straight cylindrical shank make it compatible with standard drill chucks and pneumatic drill motors frequently used in aviation maintenance and industrial settings. This bit is a general-purpose tool appropriate for professional tradespeople and skilled machinists.

Key Features

• No. 43 wire gauge size, 0.0890 inches decimal diameter for close-tolerance hole work
• 135-degree split point with self-centering geometry reduces walking and improves entry accuracy
• Cobalt tool material with straw finish for improved heat resistance in hard and abrasive materials
• 12-inch overall length provides extended reach for deep or restricted-access drilling
• Two-flute spiral design with web-thinned, tapered web for efficient chip evacuation
• Meets NAS 907 standard for aircraft extension drill bits

Compatibility

Designed as an OEM-style aircraft extension drill bit conforming to NAS 907, suitable for use in standard drill chucks and pneumatic drill motors accepting a 0.0890-inch straight cylindrical shank.

Installation Notes

This bit is installed by trained machinists, aircraft maintenance technicians, and metalworkers using standard or pneumatic drill equipment. Ensure the drill chuck is fully tightened and the shank is seated squarely before operation. Use appropriate cutting fluid or coolant when drilling hard alloys to extend bit life and maintain dimensional accuracy. Inspect the cutting edges for wear before each use and replace the bit if chipping or blunting is observed.