Hertel 01778091 Cobalt Drill Bit No. 20 135-deg Split Point

Product Description

The HERTEL 01778091 is a cobalt threaded shank drill bit designed for drilling into high-tensile strength materials where standard high-speed steel bits fall short. Built to NAS 965 specification, this bit features a 135-degree split point that reduces walking and cutting pressure on entry, making it well-suited for hard metals and tough alloys. The oxide coating adds a layer of surface protection and reduces friction during the cut. At a wire gauge size of No. 20, the cutting diameter is 0.161 inches. Overall length is 2.125 inches with a flute length of 1.125 inches. Installation is performed by licensed machinists, maintenance technicians, and trade professionals working with precision fastener holes in metal fabrication or aerospace-spec assemblies.

This bit is intended for use in materials requiring high-tensile strength drilling capability, including stainless steel, hardened alloys, and similarly demanding substrates. The 1/4-28 threaded shank connects to compatible threaded-shank holders and quick-change tooling systems. The right-hand cutting direction and regular spiral flute geometry support consistent chip evacuation during standard drilling operations. The tapered web and web-thinned geometry reduce thrust force at the tip, extending bit life in production or repetitive drilling scenarios.

Key Features

• Cobalt construction rated for high-tensile strength material applications
• 135-degree split point reduces bit walking and entry force
• Web-thinned, tapered web geometry lowers thrust and extends service life
• Oxide finish reduces friction and provides surface protection
• 1/4-28 threaded shank for use with compatible quick-change or threaded holders
• Meets NAS 965 specification
• Right-hand cut with regular spiral flute for consistent chip removal

Compatibility

Designed for use with threaded-shank tooling holders accepting a 1/4-28 thread. Suited for production and maintenance drilling in high-tensile strength metals per NAS 965 specification requirements.

Installation Notes

This bit is installed by machinists or qualified maintenance technicians using compatible threaded-shank drill holders. Ensure the holder and shank threads are clean and fully engaged before operation. Secure all tooling according to the machine manufacturer guidelines and verify spindle speed is appropriate for the workpiece material before beginning the cut. Disconnect power to the machine before changing tooling.