Hertel 66691783 Cobalt Screw Machine Drill Bit Size 2

Product Description

The HERTEL 66691783 is a cobalt screw machine length drill bit designed for heavy-duty drilling in tough materials including hardened steel, stainless steel, and high-alloy metals. Wire size 2 corresponds to a decimal diameter of 0.2210 inches. The bit features a 135-degree split point for fast, self-centering starts without a center punch, and a titanium nitride (TiN) coating that extends tool life by reducing friction and heat buildup. The straight-cylindrical shank seats securely in standard drill chucks. This is a right-hand cut bit suited for machinists, toolmakers, and maintenance technicians working with ferrous and difficult-to-machine materials.

Screw machine length drill bits are shorter than jobber-length bits, making them the preferred choice when rigidity and reduced deflection are critical. The shortened overall length of 2-7/16 inches limits runout in tight spaces and provides better control in drill presses, CNC machining centers, and hand-held power drills used in production or maintenance environments. The 1-5/16-inch flute length handles typical stock thicknesses encountered in metal fabrication, mechanical assembly, and repair operations. Web-thinned construction with a parallel web reduces thrust requirements and improves chip evacuation during drilling.

Key Features

• Cobalt construction provides heat and wear resistance for drilling hard and abrasive metals
• TiN coating reduces friction and extends cutting tool life in repetitive production use
• 135-degree split point enables self-centering starts and faster penetration
• Screw machine length (2-7/16 inches OAL) delivers added rigidity and reduced deflection
• Web-thinned, parallel web design lowers feed pressure and improves chip removal
• Right-hand cut, straight-cylindrical shank compatible with standard three-jaw chucks

Compatibility

Designed as an OEM-style replacement or standard tooling option for applications requiring wire size 2 (0.2210 inches) diameter drilling in heavy-duty metal cutting operations.

Installation Notes

Install and remove drill bits only with the drill press or power tool fully powered off and the chuck key removed from the chuck. Secure the shank fully within the chuck jaws to minimize runout. Use appropriate cutting fluid or coolant for the workpiece material when drilling ferrous metals to manage heat and extend bit life. Inspect the cutting edges and coating condition before each use and replace bits showing chipping, dulling, or coating wear.