Cleveland C04578 Drill Bit Letter W 0.386 in Hss

Product Description

The CLEVELAND C04578 is a screw machine length drill bit sized to Letter W (0.3860 inches), designed for high-speed steel general-purpose drilling in metal fabrication and machining applications. The 118-degree standard point angle and web-thinned tip reduce entry force and walking on flat or curved stock. At 3.25 inches overall length, this short-series bit fits standard drill chucks and drill presses without extension. The straight-cylindrical shank at 0.3860 inches diameter seats securely in most 3-jaw chucks. Two spiral flutes with a regular helix clear chips effectively in alloy steel and aluminum. Finish is bright/uncoated, suitable for general-purpose use in dry or lubricated cutting conditions.

This bit is built for production and maintenance drilling in alloy steel, aluminum, and similar non-ferrous and ferrous materials. The screw machine (stub) length format provides added rigidity compared to jobber-length bits, making it well-suited for drill press work, CNC turret setups, or hand-drilling in tight clearances. Machinists, tool-and-die workers, and maintenance technicians working with metal fabrication use this format regularly. The 1.875-inch flute length accommodates typical hole depths in sheet stock and structural members without requiring peck drilling in most setups.

Key Features

• Letter W size: 0.3860 inches diameter with a tolerance of +0.0000 to -0.0010 inches
• 118-degree standard point angle with web-thinned tip for reduced thrust and cleaner entry
• High-speed steel construction for general-purpose metal drilling
• Screw machine (short) length at 3.25 inches overall for increased rigidity
• Straight-cylindrical shank compatible with standard 3-jaw drill chucks
• Right-hand cut with two spiral flutes for efficient chip evacuation
• Meets ASME B94.11M standards

Compatibility

Designed as an OEM-style replacement or standard tooling addition for drill presses, CNC turret machines, and hand drills accepting straight-cylindrical shanks at 0.3860 inches. Primary workpiece materials listed by the manufacturer include alloy steel and aluminum.

Installation Notes

Installation is performed by machinists or maintenance technicians using a standard 3-jaw chuck keyed or keyless fitting. Ensure the chuck is fully tightened and the shank is fully seated before operation. Use appropriate cutting fluid for alloy steel to extend tool life and maintain tolerance. Inspect flute condition and point geometry before each use; a damaged 118-degree point should be resharpened or the bit replaced to avoid oversize holes or workpiece damage.