Value Collection GH8790313 Counterbore 31/64 in 3 Flute Hss

Product Description

The VALUE COLLECTION GH8790313 is a 3-flute interchangeable pilot counterbore designed for precision seat-cutting operations in metal fabrication and machine shop environments. Built from high-speed steel with a bright, uncoated finish, this tool accepts a 3/16-inch pilot shank and features a 31/64-inch counterbore diameter. The straight shank measures 7/16 inch in diameter and 3-1/16 inches in length, with an overall length of 4-5/16 inches. Right-hand cutting geometry makes it suitable for standard drill press and milling machine setups. Machinists and tool-and-die professionals reach for this style of counterbore when creating flat-bottomed recesses for socket head cap screws and similar fasteners.

This counterbore is suited for general metalworking applications in job shops, maintenance facilities, and production environments. The interchangeable pilot design allows the operator to swap pilots to accommodate different fastener shank sizes without replacing the body, making it a practical choice when working across varied fastener specs on a single setup. It is appropriate for use in ferrous and non-ferrous metals where a clean, flat-bottom counterbore seat is required.

Key Features

• 31/64-inch counterbore diameter for precise flat-bottom seat cutting
• 3-flute right-hand cutting geometry for smooth stock removal
• High-speed steel construction for durability across ferrous and non-ferrous materials
• Interchangeable pilot accepts 3/16-inch pilot shank for flexible fastener compatibility
• Straight 7/16-inch shank fits standard drill press and milling machine chucks
• Bright uncoated finish with overall length of 4-5/16 inches

Compatibility

Designed as an OEM-style replacement or standard addition for counterboring operations requiring a 31/64-inch diameter seat and a 3/16-inch interchangeable pilot shank on straight-shank tooling setups.

Installation Notes

This tool is installed and operated by machinists using a drill press, milling machine, or similar rotating spindle equipment. Secure the straight shank firmly in a matching chuck or collet before operation, and confirm the pilot is properly seated before beginning the cut. Always power down and lock out the machine before changing pilots or adjusting tool height. Follow applicable shop safety standards and use appropriate cutting fluid for the workpiece material to extend tool life.