Value Collection GH8860058 Solid Pilot Counterbore 0.22in Hss

Product Description

The VALUE COLLECTION GH8860058 is a solid pilot counterbore designed for creating clean, flat-bottomed recesses that seat fillister-head screws flush or below a workpiece surface. Machined from high speed steel, this 2-flute tool provides forward cutting action with a standard pilot diameter of 0.124 inches that registers in a pre-drilled hole to keep the counterbore concentric. The 0.22-inch counterbore diameter matches the bearing surface of a number 5 fillister-head screw. The straight cylindrical shank measures 0.25 inches in diameter and fits standard drill press chucks, CNC holders, and hand-held drill drivers. Machinists, tool-and-die workers, and metal fabricators are the primary users of this tool.

This counterbore is suited for light to medium metal fabrication work where a fillister-head screw must sit recessed and square to the work surface. Typical applications include machine assembly, fixture building, and sheet metal work requiring a number 5 fastener seating. The 2-flute geometry clears chips efficiently in ferrous and non-ferrous materials. With an overall length of 2.625 inches, the tool reaches into moderately deep bores without requiring an extension. It is sold individually and is well matched to benchtop drill presses or CNC machines running low-speed steel-cutting programs.

Key Features

• High speed steel construction provides hardness and wear resistance for repeated use in metal workpieces
• 0.124-inch standard pilot diameter self-registers in a pre-drilled hole for concentric counterboring
• 0.22-inch counterbore diameter sized for number 5 fillister-head screw compatibility
• 2-flute forward cutting geometry for efficient chip evacuation
• Straight cylindrical shank at 0.25 inches fits standard drill chucks and tool holders without adapters
• 2.625-inch overall length provides adequate reach for typical fixture and assembly applications

Compatibility

Designed for use with number 5 fillister-head screws. The 0.124-inch pilot diameter is sized as a standard pilot for this fastener type. Fits straight-shank tool holders and drill chucks accepting a 0.25-inch diameter shank.

Installation Notes

A licensed machinist or experienced metalworker should verify spindle speed and feed rate are appropriate for high speed steel tooling before operation. Always secure the workpiece firmly and power down the machine completely before installing or removing the counterbore from the chuck. Pre-drill the pilot hole to the correct diameter before running the counterbore to avoid tool deflection and ensure concentricity. Do not exceed the tool's rated cutting depth in a single pass on hard materials.