Hertel 42079 Cobalt Jobber Drill Bit 4.5mm 135 Deg

Product Description

The HERTEL 42079 is a cobalt jobber-length drill bit designed for drilling in hard and abrasive materials including stainless steel, hardened alloys, and high-tensile metals. Built to M35 material grade, the bit features a 135-degree split point that reduces walking and cutting pressure on entry, and an oxide and gold coating that improves lubricity and heat resistance. At 4.5 mm in diameter with an overall length of 3.15 inches (80 mm), it fits standard straight-shank chucks and is suited to bench drill presses, hand drills, and CNC drilling operations. Installation and use are handled by machinists, maintenance technicians, and metalworking tradespeople.

This bit is intended for right-hand cutting in metal fabrication, maintenance and repair, and production drilling environments. The spiral flute with regular helix promotes efficient chip evacuation in deep-hole applications. The 47 mm (1.85-inch) flute length provides adequate clearance for typical jobber-depth holes in ferrous and non-ferrous stock. The 5xD flute-to-diameter ratio makes this bit suitable for general-purpose industrial and trade use across a range of workpiece thicknesses.

Key Features

• M35 cobalt steel construction for drilling hardened and heat-resistant alloys
• 135-degree split point reduces thrust force and self-centers on entry
• Oxide and gold coating improves heat dissipation and extends cutting life
• Regular spiral flute with right-hand cutting direction for standard drilling operations
• Straight cylindrical shank fits standard drill chucks without modification
• No coolant-through design — suitable for use with external cutting fluid application

Compatibility

Designed as a standard jobber-length drill bit with a straight cylindrical shank, compatible with drill chucks accepting 4.5 mm shank diameters on bench drill presses, hand-held power drills, and CNC machining centers.

Installation Notes

Secure the workpiece firmly before drilling to prevent movement. Power down and de-energize any machine tool before changing or seating the bit in the chuck. Apply cutting fluid or oil externally when drilling ferrous metals to reduce heat buildup and extend tool life. Follow applicable shop safety standards and machine manufacturer guidelines for proper chuck torque and spindle speed selection based on material and bit diameter.