Precision Twist Drill 5998780 Screw Machine Drill Bit

Product Description

The PRECISION TWIST DRILL 5998780 is a screw machine length drill bit designed for high-performance drilling in metal fabrication and machining applications. Built from high speed steel (HSS) with a bright, uncoated finish, this bit measures 0.191 inches in diameter and delivers a 118-degree standard point angle for reliable starting and cutting accuracy. The web-thinned, tapered web construction reduces thrust and improves chip evacuation. At 2.25 inches overall length with a 1.1875-inch flute length, it fits standard screw machine drilling setups. Licensed machinists and tool-and-die professionals specify this Series R41 bit for tight-tolerance bores where controlled depth and clean entry matter.

This drill bit is suited for screw machine operations, CNC drilling, and manual drill press work on ferrous and non-ferrous metals. The primary workpiece material rating is titanium, which indicates capacity for hard and abrasive materials. The 2.5xD flute-to-diameter ratio supports chip clearing in moderate-depth holes. The straight cylindrical shank seats securely in standard drill chucks and collet holders without modification, making it practical for production runs and one-off service work alike.

Key Features

• 0.191 inch (Wire Size #11) diameter, Series R41 screw machine length
• High speed steel construction rated for titanium and other demanding workpiece materials
• 118-degree standard point angle with web-thinned, tapered web for reduced thrust
• Bright, uncoated finish — no coating to flake or delaminate under heavy use
• Regular spiral, spiral flute geometry for consistent chip evacuation
• Straight cylindrical shank fits standard chucks and collet holders
• Meets ANSI standards for geometry and dimensional accuracy

Compatibility

Designed as an OEM-style replacement and general-purpose screw machine drill bit for use in standard drill presses, CNC machining centers, and screw machine setups accepting a straight cylindrical shank in the 0.150 to 0.200 inch diameter range.

Installation Notes

Installation is performed by machinists and machine operators. Secure the shank fully in a properly sized chuck or collet before operation and verify runout is within acceptable tolerance for the application. Always power down or lock out the machine before changing tooling. Follow applicable ANSI and shop-safety standards for speed and feed selection based on workpiece material.