Hertel 4139739 Cobalt Jobber Drill 11/32 in Tialn

Product Description

The HERTEL 4139739 is a cobalt jobber-length drill bit designed for demanding holemaking in hard and abrasive materials. It carries a TiAlN coating that extends tool life by reducing heat buildup and surface wear at the cutting edge. The 135-degree split point geometry allows self-centering entry without a center punch and reduces thrust load at the start of the cut. At 4-3/4 inches overall length with a 3-7/16-inch flute, this bit fits standard drill chucks and is sized for everyday production drilling. It is suited for machinists, maintenance technicians, and fabrication shops that need a heavy-duty drill bit for high-strength steel, stainless, or cast iron.

This jobber drill is used in general metalworking and fabrication environments wherever an 11/32-inch through hole is required. Typical applications include drilling structural steel, plate, tubing, and machine components. The straight cylindrical shank seats directly in standard keyed or keyless chucks without adapters. Its regular spiral flute and right-hand cutting direction make it compatible with conventional drill presses, milling machines, and hand-held electric drills in right-hand rotation.

Key Features

• Cobalt substrate provides heat resistance for drilling hard and work-hardening alloys
• TiAlN coating reduces friction and extends cutting edge life in abrasive materials
• 135-degree split point self-centers and lowers feed pressure at breakthrough
• Web-thinned, tapered web configuration reduces torque requirement
• Straight cylindrical shank fits standard drill chucks without adapters
• Right-hand spiral flute efficiently evacuates chips from the bore

Compatibility

Designed as a jobber-series replacement drill bit for any application requiring an 11/32-inch diameter hole, compatible with standard drill press, mill, or hand-drill chucks accepting a straight cylindrical shank in the 0.3000 to 0.3500 decimal inch size range.

Installation Notes

Installation is performed by machinists or maintenance technicians familiar with drill press and hand-drill operation. Secure the shank fully in the chuck and verify concentricity before cutting. Always wear eye protection and secure the workpiece before drilling. Use appropriate cutting fluid for the material being drilled to maximize tool life and hole quality.