Precision Twist Drill 5998618 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998618 is a screw machine length drill bit designed for high-performance drilling in demanding applications. Machined from high speed steel with a coated finish, this bit features a 135-degree split point and web-thinned, tapered web construction that reduces thrust and improves chip evacuation. At 0.2055 inches in diameter (Wire Size 5) with a 2.5xD flute-to-diameter ratio, it delivers consistent, accurate hole entry. The right-hand spiral flute and straight cylindrical shank make it compatible with standard drill chucks on manual and CNC machine setups. It is rated for heavy duty use and classified as a high-performance tool under ANSI and NAS standards.

This bit is built for use in screw machine operations and short-hole drilling tasks where rigidity and precision entry matter. The screw machine length format provides added stiffness compared to jobber length bits, reducing deflection in tight-tolerance work. Primary workpiece material is titanium, making this bit suitable for aerospace, precision machining, and other hard-material applications where a split-point, web-thinned geometry is required. It is sold individually and suits professional machinists and toolroom technicians working in production or job-shop environments.

Key Features

• 135-degree split point reduces walking and lowers drilling thrust on entry
• Web-thinned, tapered web construction improves chip flow and reduces heat buildup
• High speed steel construction with coated finish for wear resistance in hard materials
• Screw machine length format provides greater rigidity and less deflection than jobber length
• Right-hand cut with regular spiral flute for standard drill press and CNC chuck use
• Meets ANSI and NAS 907 specifications for heavy duty, high-performance drilling

Compatibility

Designed as a screw machine length replacement or production-use drill bit rated for titanium and other hard primary workpiece materials, fitting any standard straight-cylindrical shank chuck within the 0.2000 to 0.2500 inch drill bit size range.

Installation Notes

This bit is installed by a machinist or toolroom technician into any drill press, turret lathe, or CNC machine equipped with a chuck accepting a straight cylindrical shank. Ensure the machine spindle is fully stopped and locked out before changing bits. Secure the shank fully in the chuck to prevent runout. Avoid side-loading the bit during drilling, as this can cause premature edge wear or bit breakage in hard materials like titanium.