Hertel 66691452 Screw Machine Drill Bit 7/16 in Cobalt

Product Description

The HERTEL 66691452 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 tough ferrous and non-ferrous materials where standard high-speed steel bits wear prematurely. The 135-degree split point reduces walking on entry and requires less thrust than conventional 118-degree points. At 3-7/16 inches overall length with a 2-1/16-inch flute length and a straight cylindrical shank measuring 0.4375 inches in diameter, it fits standard drill chucks on benchtop, floor-standing, and handheld drilling equipment. Machinists, millwrights, and maintenance technicians are the typical users.

This bit is suited for screw machine operations, CNC drilling setups, drill press work, and general metalworking where a shorter-than-jobber-length drill improves rigidity and reduces deflection. The 7/16-inch (0.4375 inch) diameter falls within the 0.4000 to 0.4500 inch heavy-duty size range. The right-hand spiral flute with regular helix evacuates chips efficiently in through-hole and blind-hole drilling. Web-thinned construction with a parallel web configuration reduces cutting resistance and extends tool life in production environments.

Key Features

• Cobalt steel construction with TiN coating for extended tool life in hard and abrasive metals
• 135-degree split point minimizes bit walking and reduces required feed force
• Web-thinned parallel web reduces cutting resistance in production drilling
• Screw machine length body improves rigidity and reduces deflection versus jobber-length bits
• Right-hand spiral flute promotes efficient chip evacuation in both through and blind holes
• Straight cylindrical shank fits standard drill chucks without adapters

Compatibility

Designed as an OEM-style replacement or direct-use screw machine drill bit compatible with any drill press, CNC machine, or handheld drill accepting a straight cylindrical shank up to 7/16 inch in diameter.

Installation Notes

Installation is performed by machinists, millwrights, or maintenance technicians familiar with rotating cutting tools. Power down and lock out the drilling machine before inserting or removing the bit from the chuck. Secure the shank fully within the chuck jaws and tighten to manufacturer-specified chuck torque before beginning any drilling operation. Use appropriate cutting fluid or coolant for the workpiece material to maximize bit life; note that this bit does not support coolant-through delivery.