Cleveland C04390 5/64 Inch Hss Screw Machine Drill Bit

Product Description

The CLEVELAND C04390 is a screw machine length (stub length) drill bit designed for high-volume drilling in tight clearance applications. Built from high-speed steel (HSS) with a bright/uncoated finish, it measures 5/64 inch (0.0781 inch) in diameter with a 118-degree standard point angle and a short overall length of 1-11/16 inches. The two-flute spiral design with a web-thinned, parallel-web configuration reduces entry resistance and helps clear chips efficiently. This bit is suited for machinists, tool-and-die shops, and general metalworking trades requiring precise, repeatable hole production in alloy steels and aluminum.

The C04390 is intended for general-purpose drilling in short-reach setups where a jobber-length bit would flex or chatter. The stub length body increases rigidity, making it well-suited for drill press work, CNC turret applications, and screw machine operations. Primary workpiece materials include alloy steel and aluminum. The straight cylindrical shank accommodates standard drill chucks without modification. This bit conforms to ASME B94.11M and meets ANSI specification requirements for drill geometry and tolerance.

Key Features

• High-speed steel construction for general-purpose metal drilling
• 118-degree standard point angle for accurate starting on flat and curved surfaces
• Web-thinned parallel web reduces thrust force and improves penetration
• Short stub length (1-11/16 inches OAL) increases rigidity and reduces deflection
• Bright/uncoated finish suitable for use with or without cutting fluid
• Diameter tolerance held to +0.0000 to -0.0005 inch for consistent hole sizing

Compatibility

Designed as a general-purpose screw machine length drill bit compatible with standard drill chucks accepting a 0.0781-inch straight cylindrical shank. Suitable for use in drill presses, CNC turret machines, and bench-top screw machine setups drilling alloy steel and aluminum workpieces.

Installation Notes

Install in a properly sized drill chuck and tighten securely before operation. Ensure the workpiece is clamped or fixtured to prevent movement during drilling. Use appropriate cutting fluid for alloy steel applications to extend tool life and maintain hole tolerance. Inspect the cutting edges for wear or chipping before each use, as a dull or damaged bit can produce oversized holes and increase thrust loads on the spindle.