Precision Twist Drill 5997255 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5997255 is a screw machine length drill bit designed for high-performance drilling in steel and cast iron. It measures 1/16 inch (0.0625 inch) in diameter with a 1-5/8 inch overall length and a 5/8 inch flute length. The 135-degree split point reduces walking on entry and lowers thrust force, making it well suited for production drilling and close-tolerance work. Manufactured from high-speed steel with a bright, uncoated finish, this bit is part of the QC41P series and features a parabolic flute geometry that promotes fast chip evacuation and reduces heat buildup during cutting.

This bit is intended for screw machine and short-hole drilling applications where a stub-length tool provides rigidity and accuracy. The parabolic flute design with a 3xD flute-to-diameter ratio makes it effective in both manual and CNC-guided drilling setups. Primary workpiece materials include steel and cast iron, making it a practical choice for machinists, maintenance technicians, and fabricators working in metal fabrication shops, HVAC equipment manufacturing, and general industrial maintenance environments. The straight cylindrical shank fits standard drill chucks without adapters.

Key Features

• 135-degree split point reduces thrust and prevents bit walk on hard metal surfaces
• Parabolic flute geometry accelerates chip evacuation and reduces heat in the cut
• Screw machine (stub) length provides increased rigidity over jobber-length bits
• High-speed steel construction handles steel and cast iron without chipping
• Web-thinned, tapered web design improves cutting efficiency at small diameters
• Straight cylindrical shank fits standard 3-jaw drill chucks directly

Compatibility

Designed as a screw machine length replacement drill bit for use in standard drill chucks accepting a 0.0625 inch straight shank, conforming to ANSI standards for stub-length HSS drill bits.

Installation Notes

Install and remove this bit only when the drill press, hand drill, or CNC spindle is fully powered down and at rest. Secure the straight shank firmly in the chuck and verify concentricity before beginning a cut to avoid deflection at this small diameter. Right-hand cutting direction requires standard forward spindle rotation. Use appropriate cutting fluid or lubricant when drilling cast iron or hard steel to extend bit life.