Precision Twist Drill 5996489 No. 9 Cobalt Drill Bit

Product Description

The PRECISION TWIST DRILL 5996489 is a screw machine length cobalt drill bit sized to No. 9 wire gauge, equivalent to 0.1960 inches in diameter. Built from M41 cobalt high-speed steel in the M41CO series, it is designed for high-performance drilling in hard and abrasive materials. The 135-degree split point reduces walking and allows drilling to start without a center punch. Web thinning further reduces thrust requirements. At 2.25 inches overall length, this stub-length bit is well suited to close-quarters drilling on short-travel drill presses, screw machines, and CNC applications where rigidity matters.

This bit is intended for metalworking and machining operations where standard HSS tooling loses its edge too quickly. Typical applications include drilling hard ferrous metals, stainless alloys, and tough workpiece materials. The screw machine length body provides added stiffness compared to a jobber-length bit, which reduces deflection and improves hole accuracy in production environments. Machinists, tool and die shops, and maintenance technicians working with hard materials are the primary users. The right-hand spiral flute with regular helix handles chip evacuation cleanly in most metal-cutting setups.

Key Features

• M41 cobalt high-speed steel construction for heat and wear resistance in hard materials
• 135-degree split point reduces thrust and eliminates walking on hard surfaces
• Web-thinned, tapered web configuration lowers cutting resistance
• Screw machine (stub) length at 2.25 inches OAL provides maximum rigidity
• Straight cylindrical shank fits standard drill chucks without additional tooling
• Right-hand cut with regular spiral flute for efficient chip evacuation

Compatibility

Designed as a direct-fit replacement or standard tooling choice for any drill chuck or screw machine spindle accepting a straight cylindrical shank of 0.1960 inches in diameter. Conforms to ANSI standards for screw machine length drill bits.

Installation Notes

Installation is performed by machinists or maintenance technicians using a standard keyed or keyless drill chuck rated for the shank diameter. Ensure the machine spindle is fully stopped and locked out before changing tooling. Secure the shank fully in the chuck to the depth of the flute relief to prevent pullout under load. Do not use this bit in hand-held portable drills for extended production runs, as the stub length is optimized for fixed-spindle machines.