Cleveland C04391 Screw Machine Drill Bit Wire 47 Hss

Product Description

The CLEVELAND C04391 is a screw machine length (stub length) drill bit designed for high-volume, close-tolerance drilling in production and machine shop environments. Built from high-speed steel with a bright/uncoated finish, it carries a 118-degree standard point angle and a web-thinned tip that reduces thrust and improves chip ejection on entry. The overall length is 1.75 inches, the flute length is 0.75 inches, and the wire gauge diameter is size 47 (0.0785 inches). The shorter body provides increased rigidity compared to jobber-length bits, making it well suited for drill press, turret lathe, and CNC applications where deflection is a concern.

This bit is intended for general-purpose drilling in alloy steel and aluminum, the primary workpiece materials listed for this series. The compact screw machine length profile fits standard drill chucks and quick-change tooling systems. It is commonly used in production machining, metal fabrication shops, and maintenance operations where wire-gauge drilling is routine. The straight cylindrical shank diameter matches the drill diameter at 0.0785 inches, allowing direct chuck mounting without adapters in most setups.

Key Features

• Wire gauge size 47 with decimal equivalent of 0.0785 inches for precise hole sizing
• 118-degree standard point angle with web-thinned tip reduces entry thrust
• High-speed steel construction handles general-purpose ferrous and non-ferrous materials
• Screw machine (stub) length body at 1.75 inches overall increases rigidity and reduces deflection
• Right-hand cut with 2-flute regular spiral for consistent chip evacuation
• Diameter tolerance held to +0.0000 / -0.0005 inches per ASME B94.11M
• Bright/uncoated finish suitable for use with or without cutting fluid

Compatibility

Designed as a general-purpose screw machine length drill bit for use in standard drill chucks, turret lathes, drill presses, and CNC machining centers that accept straight cylindrical shank tooling. Primary workpiece materials are alloy steel and aluminum as specified for the Cleveland Series 2120.

Installation Notes

Installation and use should be performed by a qualified machinist or tooling technician. Ensure the spindle and workpiece are fully secured before initiating a cut. Confirm chuck runout is within acceptable limits before use, as runout amplifies deflection at small diameters. Use appropriate cutting fluid for the workpiece material to extend tool life and maintain hole tolerance.