Cleveland C16640 Jobber Drill Bit No.28 Cobalt Tin

Product Description

The CLEVELAND C16640 is a cobalt jobber-length drill bit in wire gauge size No. 28 (0.1405 inches decimal), designed for high-performance drilling in tough materials. Built to M42 cobalt steel grade and coated with Titanium Nitride (TiN), it delivers extended tool life and superior heat resistance compared to standard HSS bits. The 135-degree split-point tip reduces walking and enables faster penetration without a center punch. The parabolic flute geometry improves chip evacuation in deep-hole drilling applications. This bit is installed and used by machinists, millwrights, and maintenance professionals working in industrial and commercial settings.

The C16640 is suited for drilling stainless steel, alloy steel, cast iron, and other hard or abrasive materials where standard high-speed steel bits underperform. Its straight-cylindrical shank accepts standard three-jaw drill chucks. The 2-7/8-inch overall length and 1-3/4-inch flute length make it appropriate for general-purpose production drilling, MRO work, and precision hole-making where tight diameter tolerance is required. Conforms to ASME B94.11M and DIN 338 standards.

Key Features

• M42 cobalt steel construction for heat and wear resistance in hard materials
• Titanium Nitride (TiN) coating extends cutting life and reduces friction
• 135-degree split-point tip eliminates walking and reduces thrust force
• Parabolic flute design promotes efficient chip removal in deeper cuts
• Web-thinned, tapered web configuration reduces cutting resistance
• Meets ASME B94.11M and DIN 338 dimensional standards

Compatibility

Designed for use in standard three-jaw drill chucks accepting a straight-cylindrical shank of 0.1405 inches diameter. Fits benchtop drill presses, CNC machining centers, and hand-held power drills configured for jobber-length bits in the No. 28 wire gauge range.

Installation Notes

Installation and use of this bit is typically performed by machinists or maintenance technicians. Secure the straight shank fully in the chuck and confirm concentricity before drilling. Always operate within the spindle speed range recommended for cobalt bits at the workpiece material and diameter. Wear appropriate eye and hand protection; do not exceed rated drill press capacity for the workpiece material.