Value Collection GH8790412 Counterbore 41/64 in 3 Flute Hss

Product Description

The VALUE COLLECTION GH8790412 is a 3-flute interchangeable pilot counterbore designed for precision enlarging and finishing of drilled holes in metalworking applications. Built from high speed steel with a bright, uncoated finish, this tool delivers reliable cutting performance across a range of ferrous and non-ferrous materials. The 41/64 inch counterbore diameter pairs with a 1/2 inch straight shank, making it compatible with standard drill press chucks and milling machine setups. Right-hand cutting geometry keeps chip evacuation predictable during operation. At 5-1/8 inches overall length and a shank length of 3-7/8 inches, it provides sufficient reach for most production and maintenance machining tasks. Installed by machinists, tool-and-die workers, and maintenance technicians.

This counterbore is suited for creating flat-bottomed recesses in workpieces to seat bolt heads, washers, or other fastener hardware flush with or below the material surface. The interchangeable pilot design allows the pilot to be swapped to match different through-hole diameters without replacing the entire tool body. Compatible pilot shank diameter for this tool is 3/16 inch. Typical applications include precision metalworking in manufacturing, aerospace maintenance, and general machine shop use where consistent counterbore depth and concentricity are required.

Key Features

• 41/64 inch counterbore diameter for accurate flat-bottom recess cutting
• 3 flutes provide balanced cutting action and effective chip clearance
• High speed steel construction handles a broad range of workpiece materials
• Straight 1/2 inch shank fits standard drill press and milling machine chucks
• Interchangeable pilot accepts 3/16 inch pilot shank for flexible hole matching
• Bright, uncoated finish with polished surfaces for reduced friction and easy inspection

Compatibility

Designed as an OEM-style replacement or direct-use counterbore for standard metalworking setups requiring a 1/2 inch straight shank and a 3/16 inch interchangeable pilot shank diameter.

Installation Notes

This tool is installed by machinists or qualified maintenance technicians using a drill press, milling machine, or compatible rotary equipment. Secure the straight shank firmly in a properly sized chuck or collet before operation and verify runout is within acceptable limits. Always power down and lock out the machine before changing pilots or removing the tool from the spindle. Follow applicable shop safety protocols and machine manufacturer guidelines when selecting feed rate and spindle speed for the workpiece material.