Keo 902-000-009 Solid Pilot Counterbore 0.26 in 3 Flute

Product Description

The KEO 902-000-009 is a solid pilot counterbore designed for precise counterboring of holes intended to seat socket-head cap screws. Machined from cobalt steel with a bright, uncoated finish, this tool delivers the hardness and heat resistance needed for production and maintenance machining. The oversize pilot measures 0.169 inches in diameter, providing positive hole alignment during the cut. The counterbore cutting diameter is 0.26 inches across 3 flutes, and the tool runs in a forward cutting direction. Overall length is 3 inches with a straight-cylindrical 7/32-inch shank. Machinists and tool-and-die technicians are the primary users.

This counterbore is sized to accept a No. 6 socket-head cap screw, making it a common selection for precision assembly work in machine shops, maintenance departments, and light manufacturing environments. The oversize pilot engages the existing drilled hole to center the counterbore accurately, reducing runout and producing a clean, flat-bottomed seat. The straight-cylindrical shank mounts directly in standard drill press or milling machine collets and chucks without adapters in most setups.

Key Features

• 0.26-inch counterbore diameter sized for No. 6 socket-head cap screws
• 0.169-inch oversize pilot for positive hole alignment and reduced runout
• 3-flute cobalt steel construction for improved heat resistance over standard HSS
• Straight-cylindrical 7/32-inch shank fits standard collets and drill chucks
• Forward cutting direction, bright uncoated finish
• 3-inch overall length provides clearance for most standard workpiece thicknesses

Compatibility

Designed for counterboring operations that seat No. 6 socket-head cap screws. Confirmed fastener size compatibility is No. 6. Consult your tooling reference for specific material and speed recommendations.

Installation Notes

Secure the workpiece firmly before starting the cut and ensure the spindle is properly zeroed. Power down the machine and lock out energy sources before changing tooling or adjusting the shank in the chuck. Use appropriate cutting fluid for the workpiece material to extend tool life. Cobalt steel tolerates higher cutting speeds than standard HSS, but avoid excessive feed rates that can chip flute edges.