Value Collection GH8860207 Solid Pilot Counterbore Hss

Product Description

The VALUE COLLECTION GH8860207 is a solid pilot counterbore designed to machine flat-bottomed recesses that seat fillister-head screws flush or below a workpiece surface. The tool has a 15/32 inch cutting diameter and a standard 5/16 inch pilot that locates precisely in a pre-drilled hole to keep the counterbore concentric. The straight cylindrical shank measures 5/16 inch in diameter and the overall length is 4 inches. Ground from high speed steel, the two-flute geometry provides clean chip evacuation in a variety of ferrous and non-ferrous materials. Machinists and toolroom technicians install this tool in drill presses, milling machines, or CNC machining centers.

This counterbore is suited for production and maintenance machining operations where fillister-head screws must be recessed into a workpiece. Typical applications include fabrication shops, machine shops, and maintenance departments working with steel, aluminum, brass, and similar machinable materials. The standard pilot style is compatible with conventionally drilled clearance holes and does not require a separate interchangeable pilot system. The 4 inch overall length provides adequate clearance for most bench and floor-standing drill press setups.

Key Features

• 15/32 inch counterbore diameter sized for fillister-head screw clearance
• Standard 5/16 inch pilot for positive hole location and concentricity
• High speed steel construction for durability across ferrous and non-ferrous workpieces
• Two-flute design promotes efficient chip removal during cutting
• Straight cylindrical 5/16 inch shank for use in standard drill chucks and collets
• Forward cutting direction compatible with standard right-hand spindle rotation

Compatibility

Designed for use with fillister-head screws requiring a 15/32 inch counterbore. Fits standard drill press, milling machine, and CNC spindles accepting a 5/16 inch straight-cylindrical shank.

Installation Notes

A licensed machinist or trained toolroom technician should install and operate this tool. Secure the workpiece firmly before engaging the spindle, and ensure the pilot diameter matches the pre-drilled clearance hole to prevent tool deflection. Use cutting fluid appropriate for the workpiece material to extend tool life. Inspect the pilot and cutting edges for wear before each use and replace the tool if chipping or excessive wear is observed.