Hertel 04138517 Cobalt Jobber Drill Bit No. 4

Product Description

The HERTEL 04138517 is a cobalt jobber-length drill bit designed for heavy-duty holemaking in ferrous and hard metals. Built to wire gauge No. 4, the bit measures 0.2090 inches in decimal diameter with a 135-degree split point that reduces walking and cutting pressure at start-up. The oxide and TiN coating provides added surface hardness and heat resistance for extended tool life under demanding conditions. At 3.75 inches overall length with a 2.5-inch flute, this is a standard jobber format suited for use in handheld drills, drill presses, and CNC setups. Right-hand spiral flutes clear chips efficiently during through-hole operations.

This bit is suited for metal fabrication, mechanical contracting, HVAC rough-in, plumbing, and electrical work where hard or stainless materials require a durable cutting tool. Its straight-cylindrical shank fits standard drill chucks without adapters. The web-thinned, tapered web design lowers thrust force, making it particularly useful for hand-drill applications in tight spaces or overhead work. Machinists, pipefitters, sheet-metal workers, and general maintenance technicians are the primary users of this format.

Key Features

• Cobalt construction rated for heavy-duty cutting in hard and abrasive metals
• 135-degree split point reduces bit walk and lowers required feed pressure
• Oxide and TiN dual coating improves surface hardness and extends service life
• Web-thinned, tapered web reduces cutting resistance during entry
• Right-hand spiral flute with regular helix for efficient chip evacuation
• Straight-cylindrical shank fits standard 3-jaw drill chucks directly

Compatibility

Designed as a standard jobber-length drill bit for use in any right-hand drill chuck accepting a 0.2090-inch straight-cylindrical shank, including handheld drills, bench drill presses, and CNC drill stations.

Installation Notes

This drill bit is installed and operated by machinists, sheet-metal workers, pipefitters, and maintenance technicians. Always secure the workpiece before drilling and set spindle speed appropriate to the material being cut. Inspect the cutting edges and coating before each use; a chipped or worn edge on cobalt tooling should not be used on hard materials. Use cutting fluid when drilling stainless or hardened steel to manage heat buildup and preserve edge life.