Precision Twist Drill 5999289 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5999289 is a screw machine length drill bit designed for high-performance drilling in tight-tolerance applications. Built from high speed steel with a bright/uncoated finish, it features a 118-degree standard point angle and a right-hand spiral flute configuration. The straight-cylindrical shank measures 0.0465 inches in diameter with an overall length of 1.375 inches and a flute length of 0.5 inches. The web-thinned, tapered web construction reduces thrust and improves chip evacuation, making this bit well-suited for production drilling environments where precision and tool life matter.

This drill bit is sized at wire gauge #56 and is rated for use in high-performance general-purpose applications, with titanium listed as the primary workpiece material. The screw machine length format — shorter than jobber length — provides added rigidity and reduced deflection in drill press, CNC, and turret lathe setups. It is commonly used by machinists, tool and die makers, and maintenance technicians working in metalworking and precision fabrication shops. The R41 series designation identifies it within the PRECISION TWIST DRILL product line as an ANSI-compliant, regular-spiral screw machine bit.

Key Features

• 0.0465-inch diameter, wire size #56, for small-hole precision drilling
• 118-degree standard point angle for general-purpose metal drilling
• Web-thinned and tapered web design reduces cutting thrust and improves chip flow
• High speed steel construction provides durability across a range of workpiece materials
• Screw machine length format adds rigidity and reduces deflection compared to jobber bits
• ANSI-compliant, Series R41, with a 2.5xD flute-to-diameter ratio

Compatibility

Designed as a screw machine length replacement or production drill bit for use in drill presses, CNC machines, turret lathes, and similar setups requiring a straight-cylindrical shank bit at the #56 wire gauge size. Primary workpiece material compatibility is listed as titanium; suitable for general-purpose metalworking applications per ANSI standards.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or tool operators familiar with small-diameter tooling. Secure the straight-cylindrical shank firmly in an appropriate collet or chuck before operation to prevent slippage or breakage. At 0.0465 inches in diameter, this bit is susceptible to breakage under excessive feed pressure or lateral load — follow the machine manufacturer's recommended feed and speed parameters for small-diameter HSS tooling. Inspect the bit for wear or damage before each use.