Precision Twist Drill 5996661 Cobalt Drill Bit 0.261 in

Product Description

The PRECISION TWIST DRILL 5996661 is a screw machine length cobalt drill bit designed for drilling into hard materials where standard high-speed steel bits fall short. Built to Series M42CO specification, this bit features an M42 cobalt material grade, a 135-degree split point for accurate self-centering starts, and a web-thinned, tapered web configuration that reduces thrust during penetration. At 0.261 inches in diameter (Letter G sizing), it delivers high-performance cutting in a compact 2-5/8 inch overall length. Licensed machinists, tool-and-die shops, maintenance mechanics, and metalworking professionals are the primary installers of this bit.

This screw machine length drill bit is suited for use in CNC machines, drill presses, and hand-held power drills where a shorter flute-to-diameter ratio is needed for rigidity and reduced deflection. The 2.5xD flute ratio and 1-7/16 inch flute length make it well matched for through-hole and blind-hole drilling in tight-clearance applications. It performs best in hard ferrous and non-ferrous materials, stainless steel, and other high-strength alloys that demand a heavy-duty, high-performance cutting tool.

Key Features

• M42 cobalt material grade rated for heavy-duty, high-performance cutting in hard materials
• 135-degree split point promotes accurate positioning and self-centering without a center punch
• Web-thinned, tapered web construction reduces feed force and heat buildup
• Screw machine (stub) length provides added rigidity and reduced deflection versus jobber-length bits
• Right-hand spiral flute geometry evacuates chips efficiently during drilling
• Straight-cylindrical shank fits standard three-jaw chucks and collet holders
• Meets ANSI specification standards for dimensional consistency

Compatibility

Designed for use in standard drill presses, CNC machining centers, and portable power drills equipped with a chuck that accepts a straight-cylindrical shank in the 0.2500 to 0.3000 inch diameter range.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or maintenance mechanics familiar with metalworking equipment. Ensure the machine is fully powered down and the chuck is secure before inserting or removing the bit. Appropriate cutting fluid or coolant is recommended when drilling hard alloys to extend tool life and manage heat, even though this bit does not support coolant-through delivery. Always verify spindle speed and feed rate are appropriate for the workpiece material and bit diameter before operation.