Precision Twist Drill 5999398 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5999398 is a screw machine length drill bit engineered for high-performance metal cutting applications. Sized at 0.302 inches in diameter (Letter N), it features a 135-degree split point for fast, accurate penetration with minimal walking on entry. The bit is manufactured from high speed steel with a coated finish to extend tool life and reduce heat buildup during cutting. At 2-13/16 inches overall length with a 1-5/8 inch flute length and a 2.5xD flute-to-diameter ratio, this is a stubby, rigid geometry designed for demanding production drilling environments. A web-thinned, tapered web configuration reduces thrust load. Licensed plumbers, machinists, and metalworking tradespeople are the primary installers and operators of this tool.

This drill bit is built specifically for primary workpiece material: titanium, making it appropriate for aerospace, industrial, and heavy-duty fabrication work where conventional bits underperform. The screw machine length (stub) design provides rigidity in drill press, turret lathe, and CNC machining center applications where a full jobber-length bit would deflect or chatter. The straight-cylindrical shank fits standard drill chucks without adapters. Series R42C is a heavy-duty designation in the PRECISION TWIST DRILL lineup, meeting ANSI and NAS 907 specifications.

Key Features

• 135-degree split point reduces walking and decreases required feed force on entry
• Web-thinned, tapered web lowers thrust load for cleaner holes in tough alloys
• High speed steel construction with coated finish for extended service life
• Screw machine (stub) length provides superior rigidity versus jobber-length alternatives
• Right-hand cut, spiral flute with 2.5xD ratio for efficient chip evacuation
• Meets ANSI and NAS 907 standards; heavy-duty Series R42C grade

Compatibility

Designed for use with standard straight-cylindrical shank drill chucks. Rated for primary workpiece material: titanium, and suitable for applications requiring ANSI and NAS 907 specification compliance. Drill bit size falls within the 0.3000 to 0.3500 decimal inch range for this series.

Installation Notes

This bit is installed by machinists, tool-and-die professionals, or qualified metalworking tradespeople using a compatible drill press, lathe turret, or CNC spindle. Secure the straight-cylindrical shank firmly in the chuck before operation and verify chuck capacity matches the 0.302-inch shank diameter. Use appropriate cutting fluid for titanium to manage heat and prevent premature edge wear. Do not exceed the recommended RPM range for the workpiece material and bit diameter as specified in standard machining data references.