Cleveland C16679 Jobber Drill Bit Letter E 1/4 in Cobalt

Product Description

The CLEVELAND C16679 is a jobber-length twist drill bit designed for heavy-duty metal drilling applications. Built from M42 cobalt high-speed steel and finished with a titanium nitride (TiN) coating, it is engineered to maintain cutting performance under high heat and friction. The bit measures 4 inches overall length with a 2.75-inch parabolic flute and a 1/4-inch straight-cylindrical shank. The 135-degree split point reduces walking on entry and allows drilling without a center punch on most metal surfaces. Machinists, tool-and-die workers, and maintenance technicians working with stainless steel, hardened alloys, and tough ferrous metals are the primary users of this series.

This bit is suited for drilling hardened steels, stainless steel, cast iron, and other high-strength alloys where standard HSS bits fail prematurely. The parabolic flute geometry improves chip evacuation in deep-hole drilling scenarios, reducing heat buildup and chip packing. Right-hand cut configuration is standard for use in conventional drill presses, CNC machines, and handheld power drills. The Series 2075T designation places this bit in a heavy-duty cobalt line intended for production and maintenance environments requiring consistent hole quality and extended tool life.

Key Features

• M42 cobalt steel construction for drilling hardened and abrasion-resistant metals
• Titanium nitride (TiN) coating reduces friction and extends cutting edge life
• 135-degree split point for self-centering entry without center punch on most metals
• Parabolic flute design improves chip evacuation in deep or interrupted cuts
• Web-thinned tapered web reduces thrust requirements and heat at the cutting tip
• Meets ASME B94.11M and DIN 338 standards for jobber-length drill geometry

Compatibility

Designed as a jobber-length replacement or production drill bit compatible with any 1/4-inch drill chuck on standard drill presses, CNC machining centers, and hand-held power drills. Straight-cylindrical shank fits keyless and keyed chuck styles without adapters.

Installation Notes

A licensed machinist or qualified maintenance technician should select appropriate spindle speed and feed rate for the workpiece material before drilling. Secure the workpiece firmly and ensure the chuck is fully tightened before operation. Use cutting fluid or coolant rated for cobalt tooling on stainless steel and high-alloy workpieces to maximize tool life, even though this bit does not have coolant-through capability. Inspect the cutting edges for wear before each use and replace if chipping or rounding is observed.