Precision Twist Drill 5999444 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5999444 is a screw machine length drill bit designed for high-performance metal cutting in demanding trade applications. Built from high speed steel with a coated finish, it features a 135-degree split point and web-thinned, tapered web construction that reduces walking and improves penetration on entry. The straight-cylindrical shank measures 5/16 inch (0.3125 inches) in diameter, and the overall length is 2-13/16 inches with a 1-5/8 inch flute length. The right-hand spiral flute geometry follows a regular spiral type and a 2.5xD flute-to-diameter ratio. This bit is rated heavy duty and is sold individually.

This drill bit is engineered for use on titanium as its primary workpiece material, making it well suited for aerospace, mechanical, and industrial fabrication tasks where hard-material drilling is required. The screw machine length format provides a shorter, more rigid profile than jobber-length bits, which improves accuracy and reduces deflection in close-quarters or high-feed-rate drilling scenarios. Machinists, millwrights, and maintenance technicians working on production or field repair applications will find this format well matched to drill press and CNC spindle use.

Key Features

• 5/16 inch (0.3125 inches) diameter with screw machine length profile for improved rigidity
• 135-degree split point reduces thrust force and minimizes center-punching requirements
• Web-thinned, tapered web construction improves chip clearance and cutting efficiency
• High speed steel construction with coated finish for extended tool life on hard materials
• Right-hand cut, regular spiral flute for standard drilling operations
• Meets ANSI and NAS 907 standards; Series R40C heavy duty classification

Compatibility

Designed for drilling titanium and other hard metals; compatible with drill presses, CNC machines, and hand-held drilling equipment fitted with a standard straight-cylindrical shank chuck in the appropriate size range.

Installation Notes

This drill bit is installed and removed by a licensed machinist or qualified tradesperson using a properly sized chuck. Always secure the workpiece before drilling and confirm the spindle speed is appropriate for the material and bit diameter. Follow applicable ANSI safety standards for rotating tool operation. Inspect the cutting edges and coating for wear before each use and replace the bit if the split point or flute edges show damage.