Cleveland C14579 Screw Machine Drill Bit No. 28 Cobalt

Product Description

The CLEVELAND C14579 is a screw machine length drill bit built for high-production drilling in tough materials. Manufactured from M42 cobalt high-speed steel, this bit handles alloy steels, aluminum, and other demanding workpiece materials where standard HSS tooling falls short. The 135-degree split point reduces walking and requires less feed pressure at entry, making it well suited for hand-held and machine drilling alike. At 1-15/16 inches overall length, the short screw machine profile provides added rigidity and reduces deflection compared to jobber-length bits. Wire size No. 28 corresponds to a decimal diameter of 0.1405 inches. Licensed tradespeople and machinists in production shops and field service use this bit regularly.

This drill bit is designed for use in screw machines, drill presses, and CNC equipment where a short, stiff bit is preferred. It performs well in alloy steels and aluminum, making it a practical choice for HVAC, plumbing, and mechanical contractors drilling through structural members, brackets, and fittings. The straight cylindrical shank fits standard chucks without adapters. Web-thinned geometry and a parallel web configuration maintain cutting efficiency through the full depth of the hole.

Key Features

• M42 cobalt construction for heavy-duty drilling in alloy steel and aluminum
• 135-degree split point reduces walking and lowers entry feed pressure
• Screw machine length at 1-15/16 inches overall for maximum rigidity and reduced deflection
• Right-hand cut with 2-flute spiral geometry for efficient chip evacuation
• Web-thinned parallel web maintains cutting performance and reduces heat buildup
• Diameter tolerance of +0.0000 to -0.0007 inches for consistent, accurate hole sizing
• Meets ASME B94.11M and DIN 1897 standards

Compatibility

Designed as an OEM-style replacement and standard tooling choice for any application requiring a wire gauge No. 28 screw machine length drill bit with a straight cylindrical shank.

Installation Notes

Install this bit in a drill press, CNC spindle, or hand drill with a chuck rated for a 0.1405-inch straight shank. Power down and lock out the machine before changing tooling. Secure the shank fully in the chuck to prevent slippage and bit breakage. Use appropriate cutting fluid for alloy steel applications to extend tool life and maintain hole quality.