Precision Twist Drill 5998513 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998513 is a screw machine length drill bit designed for high-performance drilling in demanding trade and industrial applications. Built from high speed steel (HSS) with a coated finish, this bit features a 1.25-inch diameter, a standard 118-degree point angle, and a right-hand spiral flute configuration. The straight-cylindrical shank seats securely in standard chucks. At 6.75 inches overall length with a 4.375-inch flute length, the screw machine geometry keeps the tool compact and rigid for accuracy in short-hole drilling operations. It carries ANSI standards compliance and is rated for general purpose to high performance use.

This drill bit is suited for metalworking applications where a shorter, stiffer bit is preferred over jobber length alternatives. The primary workpiece material rating is titanium, making it appropriate for aerospace, industrial maintenance, and fabrication environments where difficult-to-machine metals are common. Licensed machinists, tool and die makers, and maintenance mechanics are the typical installers. The Series R40 designation places it within a specific product family designed for consistent performance at larger diameters, particularly in the 0.6-inch-and-above size range.

Key Features

• 1.25-inch diameter with screw machine (stub) length for rigid, accurate short-hole drilling
• High speed steel construction with coated finish for extended tool life
• 118-degree standard point angle for broad material compatibility
• Right-hand cut with regular spiral flute for efficient chip evacuation
• Straight-cylindrical shank fits standard drill chucks and machine spindles
• ANSI-compliant; rated for primary use in titanium and other high-performance materials
• 2.5xD flute-to-diameter ratio for balanced rigidity and chip clearance

Compatibility

Designed as a screw machine length replacement or production drill bit for use in drill presses, CNC machining centers, and manual mills accepting a straight-cylindrical shank at 1.25-inch diameter. Primary workpiece material compatibility is rated for titanium per supplier specifications.

Installation Notes

Installation and use of this drill bit should be performed by qualified machinists or maintenance mechanics familiar with proper chuck seating and spindle speed selection for the workpiece material. Ensure the machine spindle is fully stopped and locked out before changing bits. Secure the shank fully into the chuck to the recommended grip depth to prevent slippage under load. Do not exceed the spindle speed rating appropriate for the material and bit diameter as determined by standard machining reference data.