Keo 902-000-027 Solid Pilot Counterbore 0.695in 3 Flute

Product Description

The KEO 902-000-027 is a solid pilot counterbore designed for precise, clean counterboring operations in metalworking and machining applications. Built from cobalt steel with a bright, uncoated finish, it delivers hardness and heat resistance suited for ferrous and high-strength materials. The tool features a 0.695-inch counterbore diameter, a 0.468-inch oversize pilot diameter, and three cutting flutes for efficient material removal. The straight cylindrical shank measures 0.5 inches in diameter, and the overall length is 5 inches. Forward cutting direction is standard. This tool is typically installed and used by machinists and tool-and-die professionals working on precision hole finishing.

This counterbore is sized for 7/16-inch socket-head cap screw seating, making it a practical choice for creating flat-bottomed recesses that allow fastener heads to sit flush or below a workpiece surface. It is well suited for use in manual mills, CNC machining centers, and drill press setups where accurate counterbore depth and diameter control are required. The oversize pilot helps maintain concentricity with a pre-drilled through-hole during operation.

Key Features

• Cobalt steel construction for improved hardness and heat resistance
• 0.695-inch counterbore diameter sized for 7/16-inch socket-head cap screws
• 0.468-inch oversize pilot diameter for improved concentricity
• 3-flute design for efficient chip evacuation and smooth cutting
• Straight cylindrical 0.5-inch shank for broad collet and chuck compatibility
• Bright, uncoated finish - no coating buildup to affect dimensional accuracy

Compatibility

Designed for use with 7/16-inch socket-head cap screws. Fits standard 0.5-inch shank toolholders, collets, and chucks. Specific machine or system compatibility was not stated in the product data; verify fitment with your toolholder specifications before use.

Installation Notes

This counterbore is installed and operated by machinists in milling or drilling equipment. Secure the straight shank firmly in a compatible collet or drill chuck before use, and ensure the pilot engages the pre-drilled hole cleanly to maintain concentricity. Always power down and lock out the machine spindle before changing tooling. Follow applicable shop safety standards and machine manufacturer guidelines when setting feed rates and spindle speeds for cobalt steel tooling.