Hertel C.E07.0635 Aircraft Drill Bit E 1/4 in Cobalt 12 in

Product Description

The HERTEL C.E07.0635 is a cobalt aircraft extension drill bit sized at Letter E (0.2500 inches / 1/4 inch) with a 12-inch overall length, designed for drilling in tight or deep-access applications where standard-length bits cannot reach. The 135-degree split point is self-centering and reduces walking on entry, eliminating the need for a center punch in most setups. A straw finish indicates the cobalt steel has been heat-treated, improving wear resistance and performance in harder base materials. This bit is built for professionals working in aerospace fabrication, structural metalwork, and precision mechanical trades.

The C.E07.0635 is suited for drilling ferrous and non-ferrous metals in applications requiring extended reach, such as airframe repair, deep-cavity sheet metal work, and mechanical assembly. The 2-3/4-inch spiral flute length (2.7500 inches) provides efficient chip evacuation even at depth. The straight cylindrical shank accepts standard drill chucks. Its NAS 907 compliance makes it appropriate for aerospace and military maintenance applications where documented standards are required.

Key Features

• Letter E (1/4 inch / 0.2500 inch) diameter with straight cylindrical shank of equal diameter
• 135-degree split point is self-centering and reduces thrust force on entry
• Cobalt tool steel construction with straw finish for improved heat and wear resistance
• 12-inch overall length provides extended reach for deep or obstructed drilling locations
• Two-flute right-hand spiral with web-thinned tapered web for reduced cutting resistance
• NAS 907 compliant for aerospace and defense maintenance environments

Compatibility

Designed as a general-purpose aircraft extension drill bit compatible with standard drill chucks accepting a 1/4-inch straight cylindrical shank. Meets NAS 907 standards for aerospace tooling applications.

Installation Notes

This bit is installed and used by machinists, aircraft maintenance technicians, and metalworking professionals. Secure the straight shank firmly in a keyed or keyless chuck before operation and verify chuck runout is within acceptable limits to prevent premature bit wear. Use appropriate cutting fluid for the base material to extend tool life. Inspect the split point and cutting edges for wear or chipping before each use, and never force a dull bit through material.