Keo 902-000-007 Solid Pilot Counterbore 0.228 in 3 Flute

Product Description

The KEO 902-000-007 is a solid pilot counterbore designed for precision spot-facing and counterboring operations in metalworking applications. Built from cobalt steel with a bright, uncoated finish, it offers good hardness and heat resistance for cutting ferrous and non-ferrous materials. The tool features a 0.228-inch counterbore diameter, a 0.138-inch standard pilot diameter, and three flutes for forward cutting. The straight-cylindrical shank measures 7/32 inches in diameter, and the overall length is 3 inches. Machinists and toolroom technicians use this style of counterbore when seating socket-head cap screws to a controlled depth with a clean, flat-bottomed recess.

This counterbore is sized specifically for No. 6 socket-head cap screws, making it a common tool in precision machining, fixture building, and light fabrication. It is well suited for manual drill press work and CNC operations where a dedicated pilot is preferred over a separate pilot pin. The solid pilot design keeps the tool concentric with the existing hole, reducing the chance of runout during the counterboring pass. Typical applications include steel, aluminum, and other machinable metals encountered in general machine shop environments.

Key Features

• Cobalt steel construction provides elevated heat resistance compared to standard HSS
• Solid standard pilot at 0.138 inches keeps the tool concentric with the pilot hole
• Three-flute geometry for forward cutting with good chip clearance
• Bright/uncoated finish suitable for use with cutting fluids or dry cutting
• Straight-cylindrical shank at 7/32 inches for direct chuck mounting
• Compatible with No. 6 socket-head cap screws for controlled seat depth

Compatibility

Designed for use with No. 6 socket-head cap screws. Fastener type compatibility is confirmed for socket-head cap screw applications with a standard pilot configuration.

Installation Notes

This tool is installed by a machinist or toolroom technician in a drill press, milling machine, or CNC spindle using a suitable chuck or collet that accepts a 7/32-inch straight shank. Secure the workpiece firmly before operation and ensure the pilot hole is drilled to the correct clearance diameter before counterboring. Use an appropriate cutting fluid for the workpiece material to extend tool life and improve surface finish. Inspect the pilot and cutting edges for wear before each use.