Precision Twist Drill 6001336 Letter U Aircraft Extension Drill

Product Description

The PRECISION TWIST DRILL 6001336 is a Letter U aircraft extension drill bit designed for deep-reach drilling applications in metal fabrication, aerospace maintenance, and structural assembly work. Built from high speed steel with an oxide finish, this bit measures 0.368 inches in diameter with a 3.625-inch flute length and a 6-inch overall length, giving technicians extended reach into confined spaces. The 135-degree split point is self-centering and eliminates the need for a center punch on most metal surfaces, reducing setup time and improving hole accuracy. The web-thinned, tapered web construction reduces thrust requirements during penetration. This is a general purpose, right-hand cutting drill bit suited for professional trade use.

This drill bit is built for applications where standard-length bits cannot reach, including aircraft skin drilling, structural steel work, deep-cavity drilling in HVAC equipment housings, and mechanical assembly tasks requiring extended reach. The Series 502-6 designation places it in a professional-grade line intended for shop and field technicians working with steel, aluminum, and similar metals. The straight cylindrical shank is compatible with standard drill chucks and magnetic drill setups that accept 0.368-inch shanks. It meets NAS 907 Type B standards, making it appropriate for aerospace and precision metalworking environments.

Key Features

• Letter U size — 0.368 inches diameter — for precise hole sizing in metal fabrication and aerospace work
• 135-degree split point is self-centering, reducing walkoff and eliminating center-punch steps
• 6-inch overall length with 3.625-inch flute length provides extended reach into deep or confined work areas
• High speed steel construction with oxide finish for general purpose metal drilling durability
• Web-thinned tapered web reduces drilling thrust and extends bit life in production use
• Meets NAS 907 Type B standard for aerospace and precision metalworking applications

Compatibility

Designed as an OEM-style replacement or direct-use drill bit for applications requiring a Letter U diameter straight-cylindrical shank aircraft extension drill conforming to NAS 907 Type B standards.

Installation Notes

This bit is installed and operated by machinists, aircraft maintenance technicians, and mechanical trade professionals using standard or magnetic drill equipment. Secure the straight cylindrical shank firmly in the chuck before use and verify chuck capacity accommodates a 0.368-inch shank. Use appropriate cutting fluid when drilling ferrous metals to extend bit life and maintain hole quality. Inspect the split point for wear or chipping before each use, and replace the bit if the cutting edges show signs of heat damage or deformation.