Precision Twist Drill 5998994 Drill Bit 0.358 Inch Hss

Product Description

The PRECISION TWIST DRILL 5998994 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 measures 0.358 inches in diameter and carries a 135-degree split-point angle for fast, accurate starts without center-punching. The shortened screw machine length body improves rigidity and reduces deflection in close-quarters or machine-tool setups. Web thinning further reduces cutting force at the tip, making it well suited for production drilling in hard materials. Licensed machinists, toolroom technicians, and maintenance trades typically specify this series for precision hole work.

This drill bit is rated for primary use in titanium workpieces and is appropriate for CNC drilling centers, drill presses, and manual machine setups requiring a compact, rigid bit. The R42C series is built to ANSI and NAS 907 specifications, confirming dimensional and performance standards recognized across aerospace, industrial, and heavy-duty maintenance environments. The straight cylindrical shank seats cleanly in standard drill chucks and collet systems without modification. With a flute-to-diameter ratio of 2.5xD and a 1.75-inch flute length, chip evacuation stays efficient even at higher feed rates in tough alloys.

Key Features

• 0.358 inch diameter with letter size T designation for precise hole sizing
• 135-degree split point reduces walking and lowers thrust force on entry
• Web-thinned, tapered web configuration improves chip clearance and reduces heat buildup
• Screw machine length provides increased rigidity versus jobber-length bits in tight setups
• High speed steel construction with coated finish extends service life in abrasive and hard materials
• Meets ANSI and NAS 907 standards for dimensional accuracy and performance grade

Compatibility

Designed as an OEM-style replacement and production-grade drill bit for use in standard drill chucks and collet holders accepting a straight cylindrical shank in the 0.350 to 0.400 inch diameter range, per the R42C series specification.

Installation Notes

Installation and use should be performed by qualified machinists or maintenance technicians familiar with machine tool operation. Ensure the machine spindle is fully stopped and locked out before inserting or removing the bit from the chuck or collet. Secure the shank fully within the chuck jaws or collet to the manufacturer-recommended engagement depth before operating. When drilling titanium or other hard alloys, use appropriate cutting fluid and confirm spindle speed and feed rate are within the tool manufacturer guidance for the material and diameter.