Cleveland C15117 Screw Machine Drill Bit No. 27 Cobalt

Product Description

The CLEVELAND C15117 is a screw machine length cobalt drill bit in wire size No. 27 (0.1440 inches), designed for high-production drilling in tough materials. Built to Series 2175A standards and conforming to ASME B94.11M, it features a 135-degree split point for self-centering starts without a center punch. The M42 cobalt material grade gives the bit elevated heat resistance, making it well suited for work where standard HSS bits break down prematurely. With a two-flute parabolic geometry and web-thinned parallel web, it delivers fast chip evacuation and reduced thrust. Licensed trades and machinists turn to this bit when drilling through alloy steel, aluminum, and similar materials that demand consistent dimensional accuracy.

Screw machine length drill bits are the go-to choice in production and maintenance environments where stub-length rigidity is needed without sacrificing too much reach. The C15117 fits standard drill presses, CNC machining centers, and portable electric drills with a straight-cylindrical shank. Its compact 2-1/16 inch overall length reduces deflection in close-clearance setups. Primary workpiece materials include alloy steel and aluminum, making it a practical choice for automotive, HVAC equipment fabrication, and general mechanical assembly work.

Key Features

• No. 27 wire size, 0.1440 inch diameter with a tight tolerance of +0.0000 to -0.0007 inches
• M42 cobalt material grade for superior heat and wear resistance over standard HSS
• 135-degree split point enables self-centering entry and reduces walking on flat surfaces
• Parabolic two-flute design with web thinning promotes fast chip removal and lower cutting force
• Screw machine (stub) length at 2-1/16 inches OAL maximizes rigidity and minimizes deflection
• Straight-cylindrical shank fits standard drill chucks without adapters
• Meets ASME B94.11M dimensional standards under ANSI specification designation

Compatibility

Designed as an OEM-style replacement or direct-use screw machine drill bit for standard drill chucks and collet holders accepting a 0.1440 inch straight-cylindrical shank. Rated for drilling alloy steel and aluminum workpieces.

Installation Notes

Install in a properly sized drill chuck or collet and confirm secure seating before operation. Always wear appropriate eye protection and secure the workpiece before drilling. Match spindle speed to the workpiece material and bit diameter per standard machining tables. Inspect the cutting edges before each use and replace the bit if chipping or excessive wear is present.