Hertel 04138780 Cobalt Jobber Drill No 31 135 Deg

Product Description

The HERTEL 04138780 is a cobalt jobber-length drill bit sized to wire gauge No. 31 (0.1200 inches decimal). It is designed for holemaking in ferrous and hard materials where standard high-speed steel bits wear prematurely. The 135-degree split point reduces walking on entry and lowers thrust force, making it well-suited for production drilling without a center punch. The oxide and TiN coating combination improves surface hardness and reduces friction during the cut. At 2.75 inches overall length with a 1.625-inch flute, this is a standard jobber geometry built for general-purpose use in machine shops, fabrication, and mechanical service work.

This drill bit fits typical hand-held power drills, drill presses, and CNC machining centers accepting a 0.1200-inch straight cylindrical shank. The right-hand spiral flute with regular helix and tapered web configuration makes it appropriate for drilling mild steel, stainless steel, cast iron, and other tough alloys encountered in HVAC equipment fabrication, plumbing rough-in, and electrical panel work. It is sold individually per package with a minimum order quantity of 12 units, making it practical for shop stocking or field kit replenishment.

Key Features

• Cobalt construction resists heat and wear in hard and abrasive materials
• 135-degree split point reduces drill walk and lowers required thrust force
• Oxide and TiN coating improves hardness and reduces cutting friction
• Web-thinned, tapered web configuration improves chip evacuation
• Straight cylindrical shank fits standard 3-jaw chucks without adapters
• Heavy-duty grade jobber series rated for demanding production and service applications

Compatibility

Designed as a standard jobber-length drill bit for use in any drill press, hand-held power drill, or machining center accepting a 0.1200-inch straight cylindrical shank.

Installation Notes

Secure the shank fully in the chuck before operation and confirm chuck key is removed before starting the spindle. Use appropriate cutting fluid or coolant when drilling stainless steel or hard alloys to extend tool life. Inspect the cutting edges before each use and replace bits that show chipping or heat discoloration. Drilling speed and feed should be matched to the workpiece material per standard machining reference data.