Hertel 66691288 Screw Machine Drill Bit 11/64 Cobalt Tin

Product Description

The HERTEL 66691288 is a screw machine length drill bit designed for high-production drilling in metal fabrication, machining, and maintenance applications. Built from cobalt steel with a titanium nitride (TiN) coating, this bit handles hard ferrous metals, stainless steel, and high-temperature alloys that would wear out standard HSS tooling. The 135-degree split point reduces walking and lowers thrust requirements, making it well suited for hand drilling or drill press work. At 2.125 inches overall length with a 1.0625-inch flute, the shortened screw machine profile fits rigid setups where stub length is preferred for accuracy and rigidity.

This drill bit is used in metalworking shops, HVAC fabrication, plumbing rough-in, and electrical panel work wherever precise, clean holes are needed in steel or hard alloys. The straight cylindrical shank seats directly in standard three-jaw chucks and quick-change drill holders without adapters. Right-hand spiral flute geometry pulls chips away from the cutting edge during penetration, reducing heat buildup in the workpiece.

Key Features

• Cobalt construction with TiN coating extends tool life in hard and abrasive metals
• 135-degree split point starts on contact, eliminating center-punch requirements on most materials
• Web-thinned, parallel web configuration reduces cutting resistance and heat
• Screw machine length overall length of 2.125 inches provides enhanced rigidity over jobber-length bits
• Straight cylindrical shank diameter of 0.1719 inches fits standard chucks directly
• Right-hand spiral flute promotes chip evacuation and reduces recutting

Compatibility

Designed as a heavy-duty screw machine length drill bit for use in standard three-jaw chucks and drill press setups capable of accepting a 0.1719-inch straight cylindrical shank.

Installation Notes

Installation and use should be performed by machinists or trade professionals familiar with drilling operations. Secure the workpiece fully before drilling to prevent rotation or movement. Use appropriate cutting fluid when drilling stainless steel or high-hardness alloys to extend bit life and control heat. Inspect the cutting edges before each use and replace the bit if chipping or excessive wear is observed.