Precision Twist Drill 6001207 Aircraft Extension Drill Bit

Product Description

The PRECISION TWIST DRILL 6001207 is a high speed steel aircraft extension drill bit designed for deep-reach drilling in metal fabrication, aerospace maintenance, and structural applications. The 31/64 inch (0.4844 inch decimal) diameter bit features a 135-degree split point for self-centering starts without a center punch, reducing walking on hard or coated surfaces. The oxide finish provides mild corrosion resistance and reduces friction during cutting. With a 4.375-inch spiral flute length and a 6-inch overall length, this bit reaches fastener locations inaccessible to standard-length drills. It is installed and operated by machinists, aircraft maintenance technicians, and structural tradespeople working with steel, aluminum, and similar materials.

This drill bit is suited for through-hole and clearance-hole work in aircraft structures, structural steel, and sheet metal assemblies where extended reach is required. The straight-cylindrical shank seats directly in standard drill chucks and extension holders without adapters. The Series 500-6 designation places this bit in a product family built to NAS 907 Type B standards, which define dimensional and performance requirements for aircraft-quality extension drills. It is appropriate for both production drilling and field maintenance use.

Key Features

• 135-degree split point with web thinning for self-centering and reduced thrust force
• 31/64 inch diameter (0.4844 inch decimal) straight-cylindrical shank fits standard chucks
• 4.375-inch flute length provides extended reach into deep or obstructed bore locations
• High speed steel construction handles steel, aluminum, and general-purpose metal drilling
• Oxide finish reduces surface friction and offers basic corrosion protection
• Meets NAS 907 Type B standard for aircraft-quality extension drill dimensions and performance
• Right-hand cutting, 2-flute spiral design with tapered web configuration

Compatibility

Designed as an OEM-style replacement or direct-use aircraft extension drill bit conforming to NAS 907 Type B standards, compatible with standard drill chucks and extension holders accepting a 31/64 inch straight-cylindrical shank.

Installation Notes

Secure the straight-cylindrical shank firmly in a drill chuck or extension holder before use, verifying there is no runout that could cause bit deflection. Disconnect or de-energize the drill prior to bit changes. Use appropriate cutting fluid or lubrication when drilling steel to extend tool life and prevent heat buildup. Wear eye protection and secure the workpiece per standard shop safety practices.