Hertel 42166 Cobalt Jobber Drill Bit 15/32 in 135 Deg

Product Description

The HERTEL 42166 is a cobalt jobber length drill bit designed for drilling into hard and abrasive materials including stainless steel, high-alloy steels, cast iron, and heat-treated metals. Built from M35 cobalt high-speed steel, this bit maintains hardness and cutting edge integrity under elevated heat conditions that standard HSS bits cannot handle. The 135-degree split point geometry reduces walking and allows drilling to start without a center punch in most applications. The bright uncoated finish is appropriate for general-purpose use across a wide range of materials. With a 5.75-inch overall length and a 4-5/16-inch flute length, this is a standard jobber-series geometry suited for drill press, handheld, and CNC drilling operations.

This drill bit is used in metalworking, fabrication, mechanical contracting, and maintenance applications where harder-than-average base materials are encountered. The right-hand cutting direction and regular spiral flute make it compatible with standard drill chucks and machines. Typical applications include drilling through structural steel, heavy-gauge sheet metal, stainless fastener clearance holes, and similar work found in commercial HVAC installation, plumbing rough-in on steel framing, and electrical panel work. The straight cylindrical shank fits standard 3-jaw chucks without modification.

Key Features

• M35 cobalt high-speed steel construction for heat resistance and edge retention in hard metals
• 135-degree split point reduces bit walking and lowers thrust required at drill start
• 4-5/16-inch spiral flute length provides efficient chip evacuation on deeper passes
• Right-hand cut with regular spiral geometry compatible with standard drill equipment
• Bright uncoated finish suitable for use with cutting fluid across varied materials
• Straight cylindrical shank fits standard 3-jaw drill chucks without adapters

Compatibility

Designed as a standard jobber length drill bit with a straight cylindrical shank, this bit fits any drill press, handheld drill, or CNC machine equipped with a 3-jaw or collet chuck sized for a 15/32-inch shank diameter.

Installation Notes

Installation of this bit is performed by machinists, fabricators, and trade professionals including HVAC technicians, plumbers, and electricians. Secure the straight shank firmly in the chuck before operation and confirm the drill is set to right-hand rotation. Use an appropriate cutting fluid or lubricant when drilling stainless steel or other work-hardening alloys to extend bit life and reduce heat buildup. Never force the bit through material at excessive feed rates, as cobalt bits are harder but more brittle than standard HSS and can fracture if side-loaded.