Precision Twist Drill 5995968 Cobalt Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5995968 is a cobalt screw machine length drill bit engineered for drilling hard and abrasive materials in high-demand shop and field applications. Built to the M40CO series specification, it features a 35/64 inch (0.5469 inch) diameter, a 135-degree split point for fast penetration and reduced walking, and a web-thinned tapered web construction that lowers thrust requirements on tough workpieces. The straight-cylindrical shank seats securely in standard drill chucks and screw machine spindles. At 4 inches overall length with a 2.5 inch flute length, this bit is designed for stub-length rigidity in production environments. Installation is performed by machinists, tool-and-die technicians, and maintenance trades working with hard ferrous and non-ferrous stock.

This bit is suited for screw machine operations, CNC drilling centers, drill presses, and handheld applications where a stubby, rigid cutting tool is required to maintain accuracy in hard material. The cobalt construction handles elevated cutting temperatures without sacrificing edge hardness, making it appropriate for stainless steel, hardened alloys, and other hard workpiece materials. The right-hand spiral flute provides efficient chip evacuation during deep-hole passes. It carries ANSI specification designation and is graded heavy duty for sustained production use.

Key Features

• Cobalt (M40 grade) construction resists heat and wear when cutting hard materials
• 135-degree split point reduces thrust and eliminates center-punch requirements on most setups
• Web-thinned tapered web lowers cutting resistance and improves chip flow
• Screw machine (stub) length at 4 inches overall provides extra rigidity over jobber-length bits
• 2.5xD flute-to-diameter ratio supports controlled chip evacuation in blind and through holes
• ANSI-conforming geometry for consistent dimensional accuracy across production runs

Compatibility

Designed as a heavy-duty OEM-style replacement or production drill bit for use in screw machines, drill presses, and CNC spindles accepting a straight-cylindrical shank in the 0.5000 to 0.6000 inch diameter range.

Installation Notes

Installation is performed by machinists or maintenance technicians. Ensure the machine spindle or drill chuck is fully de-energized and locked out before changing tooling. Seat the straight-cylindrical shank fully into the chuck and tighten evenly to prevent runout. Coolant-through is not supported on this bit, so use external flood or mist coolant when drilling hard ferrous materials to maintain edge life.