Cleveland C46121 Countersink 5/8 in 90 Degree Hss

Product Description

The CLEVELAND C46121 is a single-flute high speed steel countersink designed for creating accurately angled seat profiles in metal workpieces. It produces a 90-degree included angle with a 5/8-inch head diameter, making it well suited for deburring drilled holes and seating flat-head fasteners flush to the surface. The straight-cylindrical shank measures 3/8 inches in diameter for secure chuck engagement. An oxide coating provides surface hardness and helps resist wear during repeated use. This tool is intended for use by machinists, fabricators, and tool-and-die professionals working with carbon steel and cast iron stock.

The C46121 is commonly used in machine shops, metal fabrication facilities, and maintenance environments where countersinking operations are performed on carbon steel and cast iron components. Its single-flute geometry reduces chatter and produces clean, consistent seat angles in applications where controlled material removal is important. The 3/8-inch shank fits standard drill press chucks and CNC toolholders, making it adaptable to both manual and automated operations.

Key Features

• 90-degree included angle (45-degree centerline angle) for standard flat-head fastener seating
• 5/8-inch head diameter suitable for a range of fastener sizes
• Single-flute design minimizes chatter and promotes clean cuts
• High speed steel construction withstands heat generated in production cutting
• Oxide finish adds surface protection and reduces friction during cutting
• Straight-cylindrical 3/8-inch shank fits standard drill press and CNC chucks

Compatibility

Designed for countersinking operations in carbon steel and cast iron. Fits drill presses, milling machines, and CNC machining centers equipped with a 3/8-inch or larger chuck or collet system. No pilot included; intended for use without a piloted guide bushing.

Installation Notes

Installation and use should be performed by qualified machinists or metalworking professionals. Secure the shank firmly in the chuck before operation and verify zero runout to ensure a clean seat angle. Always reduce spindle speed when transitioning to countersinking from drilling to avoid tool deflection and surface chatter. Inspect the cutting edge before each use and replace the tool if chipping or excessive wear is observed.