Cleveland C04550 Screw Machine Drill Bit 21/64 Hss

Product Description

The CLEVELAND C04550 is a screw machine length (stub length) drill bit designed for high-volume drilling in metal fabrication, machining, and maintenance applications. Built from high-speed steel (HSS) with a bright/uncoated finish, this bit measures 21/64 inches (0.3281 inches) in diameter with a 2-15/16 inch overall length and a standard 118-degree point angle. The shortened flute length and rigid body reduce deflection and improve hole accuracy in production environments. Web thinning reduces thrust and makes starting the cut cleaner, particularly in harder alloys. Licensed machinists, tool-and-die techs, and maintenance mechanics are the primary users of this format.

The C04550 is suited for general-purpose drilling in alloy steel, aluminum, and similar workpiece materials where a shorter, stiffer bit is preferred over jobber-length tooling. The straight cylindrical shank fits standard drill chucks on drill presses, CNC machining centers, and hand-held electric drills. Its 2-flute right-hand spiral geometry provides efficient chip evacuation during through-hole and blind-hole operations in both ferrous and non-ferrous materials.

Key Features

• 21/64 inch (0.3281 inch) diameter with a tight tolerance of +0.0000 to -0.0010 inches for consistent hole sizing
• 118-degree standard point angle with web thinning for reduced thrust and easier entry
• High-speed steel construction for heat resistance during general-purpose metal cutting
• Screw machine (short) length at 2-15/16 inches OAL reduces deflection versus jobber-length bits
• Straight cylindrical shank (0.3281 inch shank diameter) fits standard drill chucks without adapters
• Right-hand cut, 2-flute spiral geometry for efficient chip clearance in alloy and aluminum
• Meets ASME B94.11M dimensional standards for drill bit geometry and tolerances

Compatibility

Designed as a general-purpose screw machine length drill bit in the Cleveland Series 2120, suitable for use in standard drill chucks accepting straight cylindrical shanks across drill presses, CNC machines, and portable electric drills.

Installation Notes

This bit is installed and removed by a licensed machinist or qualified maintenance technician using a standard chuck key or keyless chuck system — ensure the chuck is fully tightened before operation. Always power down and lock out the machine before changing tooling. Use appropriate cutting fluid when drilling alloy steel to extend tool life and reduce heat buildup. Do not exceed the recommended feed and speed parameters for the workpiece material and bit diameter.