Hertel 66691239 Screw Machine Drill Bit 3/32 in Cobalt

Product Description

The HERTEL 66691239 is a screw machine length drill bit designed for high-speed drilling in metal fabrication, machining, and maintenance applications. Built from heavy-duty cobalt steel with a titanium nitride (TiN) coating, this bit delivers extended tool life and heat resistance in demanding materials including stainless steel, cast iron, and hardened alloys. It measures 3/32 inch (0.0938 inch) in diameter with a 1-3/4 inch overall length and a 3/4 inch flute length. The 135-degree split point geometry reduces walking on entry, eliminating the need for a center punch in most applications. The web-thinned, parallel web configuration reduces thrust and improves chip evacuation.

This drill bit is suited for screw machine operations, CNC drilling, and bench drill press work where a shorter flute length provides rigidity and accuracy. The right-hand spiral flute design is standard for conventional rotating spindles. Machinists, tool-and-die technicians, and maintenance professionals in HVAC, plumbing, and electrical trades use this bit for sheet metal, structural steel, and component fabrication work requiring tight tolerances. The straight-cylindrical shank fits standard three-jaw chucks without modification.

Key Features

• Cobalt construction with TiN coating for extended wear resistance in hard and abrasive materials
• 135-degree split point reduces drill walking and entry thrust
• Web-thinned parallel web improves chip flow and reduces cutting resistance
• Screw machine length (1-3/4 inch OAL) provides increased rigidity over jobber-length bits
• Right-hand cut, spiral flute for use in standard rotating spindles
• Straight-cylindrical shank fits conventional three-jaw chucks directly

Compatibility

Designed as an OEM-style replacement or direct-use drill bit for any standard three-jaw chuck or collet accepting a 0.0938-inch straight-cylindrical shank in screw machine, CNC, or drill press applications.

Installation Notes

Installation is performed by machinists or trade professionals using a standard three-jaw chuck or compatible collet system. Ensure the spindle is fully powered down and the chuck key is removed before inserting or changing bits. Secure the shank firmly to the full recommended grip depth to prevent slippage during high-torque operations. Always wear appropriate eye protection and follow applicable shop safety standards when operating drill press or CNC equipment.