Value Collection GH8840449 Counterbore 11/16 in 4 Flute Hss

Product Description

The VALUE COLLECTION GH8840449 is an interchangeable pilot counterbore designed for precision enlarging and seating of bolt holes in metal fabrication and aerospace-style applications. Built from high-speed steel with a bright, uncoated polished finish, this tool features a 11/16 inch counterbore diameter, a 1/4 inch straight shank, and 4 flutes for efficient chip evacuation and clean cutting action. The 3-1/8 inch overall length provides adequate reach for standard workpiece thicknesses. Right-hand cutting geometry makes it compatible with conventional drill press and mill setups used by machinists, maintenance technicians, and aerospace assembly professionals.

This counterbore is suited for aircraft-style applications where interchangeable pilot systems are standard practice. The interchangeable pilot design allows the operator to swap pilot sizes to match different fastener clearance holes without replacing the body, making it a versatile tool for shops that work across multiple hole sizes. It is appropriate for use in ferrous and non-ferrous metals in both production and maintenance environments. The 3/16 inch pilot shank diameter compatibility defines the pilot used during operation.

Key Features

• 11/16 inch counterbore diameter for accurate bolt-seat enlargement
• High-speed steel construction for durability across ferrous and non-ferrous materials
• 4 flutes for efficient chip clearing and smooth finish
• Interchangeable pilot system accepts 3/16 inch pilot shank for versatile use
• Bright, uncoated polished finish — no coating to chip or delaminate
• Aircraft-style design for use in aerospace and precision fabrication workflows

Compatibility

Designed for use with interchangeable pilot counterbore systems that accept a 3/16 inch pilot shank diameter. Fits standard straight-shank toolholders with a 1/4 inch bore.

Installation Notes

This tool is installed and operated by machinists or maintenance technicians using a drill press, milling machine, or hand-held power tool with an appropriate chuck or collet. Secure the workpiece firmly before operation and verify the pilot shank is fully seated before beginning the cut. Run at speeds appropriate for high-speed steel in the material being machined — consult published HSS cutting speed tables for the specific material. Do not use without a pilot in place, as an unsupported counterbore body will produce an inaccurate seat.