Hertel 912 37 Aircraft Extension Drill Bit No 37 Hss

Product Description

The HERTEL 912 37 is a No. 37 wire-size aircraft extension drill bit designed for reaching deep or obstructed bore locations that standard-length bits cannot access. Built from high-speed steel with an oxide finish, this bit features a 135-degree split point that is self-centering and eliminates the need for a center punch on most materials. The two-flute spiral design with a web-thinned, tapered web reduces cutting resistance and helps clear chips efficiently. At 12 inches overall length, it gives tradespeople and machinists the reach needed for airframe, HVAC duct, and structural drilling applications.

This bit is suited for general-purpose drilling in metal, plastic, and composite materials where extended reach is required. Common install scenarios include drilling through deep structural members, HVAC equipment cabinets, electrical enclosures, and sheet metal assemblies where access is restricted. The straight cylindrical shank seats securely in standard drill chucks and right-angle drill adapters commonly used in tight-clearance work. Right-hand cutting direction is standard for conventional drill press and handheld drill use.

Key Features

• No. 37 wire size, 0.1040 inch decimal diameter for precision-toleranced holes
• 135-degree split point is self-centering and reduces walking on hard surfaces
• 12-inch overall length provides extended reach into deep or restricted spaces
• High-speed steel construction with oxide finish for corrosion and heat resistance
• Two-flute spiral design with web-thinned tapered web for reduced thrust and efficient chip evacuation
• Right-hand cutting, straight cylindrical shank fits standard chucks and right-angle adapters

Compatibility

Designed as a general-purpose aircraft extension drill bit compatible with standard drill chucks and right-angle drill adapters accepting a 0.1040-inch straight cylindrical shank.

Installation Notes

Installation should be performed by qualified machinists, HVAC technicians, or electricians familiar with rotary cutting tools. Secure the shank fully in the chuck before drilling and confirm the workpiece is clamped or fixtured to prevent movement. Use cutting fluid on ferrous metals to extend bit life and reduce heat buildup. Inspect the cutting edges before each use and replace the bit if chipping or dulling is observed.