Cleveland C46439 Counterbore 3/4 Inch 3 Flutes Hss

Product Description

The CLEVELAND C46439 is an interchangeable pilot counterbore designed for precision recess machining in metal fabrication and machine shop environments. Built from high-speed steel with a bright, uncoated finish, this tool delivers reliable cutting performance across a range of ferrous and non-ferrous materials. It features a 3/4 inch counterbore diameter, a 1/2 inch straight shank, and 3 cutting flutes arranged for right-hand cutting direction. The overall length is 5-3/8 inches with a shank length of 3-7/8 inches. Machinists, tool and die makers, and maintenance technicians install this counterbore in manual mills and CNC setups where bolt-head or fastener-seat recesses are required.

This counterbore is suited for use on alloy tool steel, aluminum, cast iron, low-carbon steel, and medium-carbon steel workpieces. The interchangeable pilot design accepts a 1/4 inch pilot shank, allowing the tool body to be reused with different pilot sizes for versatile application across multiple bore diameters. Typical use cases include counterboring bolt clearance holes on structural assemblies, machine frames, and fabricated components where a flat-bottomed recess is required for flush or recessed fastener seating.

Key Features

• 3/4 inch counterbore diameter with 3-flute geometry for smooth, efficient material removal
• High-speed steel construction provides durability across alloy steel, aluminum, cast iron, and carbon steel applications
• Interchangeable pilot design accepts a 1/4 inch pilot shank for flexible use across multiple setups
• 1/2 inch straight shank fits standard mill collets and drill press chucks
• Bright, uncoated finish with polished surfaces for reduced friction during cutting
• Right-hand cutting direction compatible with standard spindle rotation

Compatibility

Compatible with 1/4 inch interchangeable pilot shanks. Designed as an OEM-style counterbore replacement for machine shop and maintenance applications requiring a 3/4 inch counterbore diameter with a 1/2 inch straight shank interface.

Installation Notes

Installation is performed by machinists or tool and die technicians using a milling machine or drill press. Secure the 1/2 inch shank firmly in a collet or chuck rated for the shank diameter before operation. Ensure the interchangeable pilot is properly seated and locked before engaging the workpiece. Follow applicable shop safety procedures, including machine guarding and spindle speed selection appropriate for the workpiece material and tool diameter.