Hertel 84024124 Cobalt Drill Bit 5/16 in 135 Point 1/4-28

Product Description

The HERTEL 84024124 is a short-series cobalt drill bit with a threaded shank designed for drilling into high-tensile strength metals. It measures 5/16 inches in diameter with a 1.25-inch overall length and a 9/16-inch spiral flute length. The 135-degree split point geometry reduces the force needed to start a hole and minimizes walking on hard surfaces. The oxide coating adds surface hardness and light corrosion resistance. The tapered web and web-thinning treatment reduce thrust load during penetration. Right-hand cutting with a regular spiral flute, this bit is built for production-environment drilling where tool life in tough alloys matters.

This drill bit is suited for aerospace and industrial metalworking applications involving high-tensile strength metals such as stainless steel, titanium, and high-alloy steels. The 1/4-28 threaded shank is compatible with quick-change threaded adapters and drill holders common in production drill press and CNC setups. It meets NAS 965 Type D specification, making it appropriate for close-tolerance hole work in aerospace and defense fabrication environments. The short overall length improves rigidity and reduces deflection in materials that work-harden quickly.

Key Features

• Cobalt construction with oxide coating for durability in high-tensile strength metals
• 135-degree split point reduces thrust and prevents bit walking at hole start
• Web-thinned tapered web lowers drilling resistance and heat buildup
• 1/4-28 threaded shank fits standard quick-change drill holders
• NAS 965 Type D specification for close-tolerance aerospace applications
• Right-hand spiral flute with regular helix for consistent chip evacuation

Compatibility

Designed for use with 1/4-28 threaded quick-change drill adapters and holders. Best suited for drilling high-tensile strength metals per NAS 965 Type D application requirements.

Installation Notes

Installation and use should be performed by qualified machinists or trade professionals familiar with drill press, hand drill, or CNC spindle setups. Secure the threaded shank fully into the adapter before operation to prevent slippage. Always wear appropriate eye and hand protection when drilling metal. Ensure workpiece is clamped firmly and use a cutting fluid appropriate for the base material to extend bit life and maintain hole quality.