Precision Twist Drill 5995952 Cobalt Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5995952 is a cobalt screw machine length drill bit designed for drilling into hard and abrasive materials where standard high-speed steel bits fall short. Built to Series M40CO specifications, it features a 135-degree split point that reduces walking on contact and lowers the thrust needed to start the hole. The straight-cylindrical shank seats securely in standard drill chucks and machine spindles. The spiral flute geometry runs at a 2.5xD ratio, promoting chip evacuation in short, confined bores. This bit is a go-to tool for machinists, maintenance techs, and fabricators working on hard-material applications.

Screw machine length drill bits are shorter than jobber-length bits, which makes them stiffer and better suited for drilling on lathes, screw machines, CNC machining centers, and drill presses where rigidity and concentricity matter. The 0.4531-inch diameter places this bit in the 29/64-inch fractional size range. Its compact overall length keeps deflection to a minimum when drilling hard stock, stainless steel, high-nickel alloys, or other tough workpiece materials. Web thinning on the tapered web reduces cutting resistance at the point, which extends tool life in high-cycle production environments.

Key Features

• Cobalt M40 material grade for heat resistance and durability in hard-material drilling
• 135-degree split point reduces drill walk and lowers entry thrust
• Web-thinned tapered web decreases cutting resistance and extends tool life
• Screw machine length body provides added rigidity over jobber-length bits
• 2.5xD flute-to-diameter ratio supports chip evacuation in short-bore applications
• Meets ANSI standards for dimensional consistency and interchangeability

Compatibility

Designed as a heavy-duty OEM-style replacement or direct-application drill bit for use in standard straight-shank drill chucks, lathe tailstocks, and CNC tool holders accepting a 0.4531-inch straight-cylindrical shank. Falls within the 0.4500 to 0.5000 inch drill bit size range of the M40CO series.

Installation Notes

A qualified machinist or tool-and-die technician should install and operate this bit using equipment rated for the shank diameter. Secure the shank fully in the chuck or collet before powering the machine, and confirm chuck key removal before spindle activation. Do not exceed the machine spindle speed recommended for cobalt tooling in the target workpiece material. Coolant-through is not supported on this bit; use external flood or mist coolant when drilling hard or heat-sensitive materials.