Precision Twist Drill 5999433 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5999433 is a screw machine length drill bit designed for high-performance drilling in demanding trade and industrial applications. Built from high speed steel with a coated finish, this bit features a 135-degree split point that reduces walking and improves hole entry accuracy. The web-thinned, tapered web construction lowers thrust requirements and helps maintain cutting efficiency through harder materials. At 21/64 inch (0.3281 inches) in diameter with an overall length of 2-15/16 inches and a flute length of 1-11/16 inches, it fits standard drill chucks and is sized for precision work where a jobber-length bit would be too long or too flexible.

This drill bit is rated for use on titanium as its primary workpiece material, making it a strong choice for aerospace, HVAC component fabrication, and mechanical contractors working with corrosion-resistant alloys. The screw machine length body provides added rigidity in drill press, CNC turret, and hand-drill applications where shorter reach reduces deflection. The Series R40C designation identifies it as a heavy duty bit meeting ANSI and NAS 907 specifications, suited for shops and field technicians who need consistent performance across production runs or repetitive service work.

Key Features

• 21/64 inch (0.3281 inches) diameter with a 2.5xD flute-to-diameter ratio for chip clearance
• 135-degree split point reduces thrust and eliminates center-punch requirements on most metals
• Web-thinned tapered web lowers cutting resistance in titanium and hard alloys
• Screw machine length body increases rigidity and reduces deflection versus jobber-length bits
• Right-hand spiral flute with straight-cylindrical shank fits standard drill chucks and collets
• Meets ANSI and NAS 907 specifications for heavy duty, high-performance tooling

Compatibility

Designed as an OEM-style replacement or direct-use drill bit for applications requiring screw machine length tooling in Series R40C; fits any standard drill chuck or collet accepting a straight-cylindrical shank in the 21/64 inch size range.

Installation Notes

Installation and use should be performed by qualified machinists, tool and die technicians, or mechanical contractors familiar with drill press and hand-drill safety practices. Secure the workpiece firmly before drilling and confirm the chuck is tightened to prevent bit slippage. When drilling titanium or hard alloys, use appropriate cutting fluid to extend tool life and manage heat buildup. Inspect the cutting edges before each use and replace the bit if chipping or excessive wear is observed.