Cleveland C91734 Solid Pilot Counterbore 1-1/32 in Hss

Product Description

The CLEVELAND C91734 is a solid pilot counterbore designed for creating precision-finished counterbore holes in metalworking applications. Built from high-speed steel (HSS) with a bright, uncoated finish, it features a 1-1/32 inch cutting diameter and a 25/32 inch standard pilot that registers directly in a pre-drilled hole to keep the counterbore concentric. The straight-cylindrical shank measures 1 inch in diameter, and the tool runs 8-13/16 inches in overall length. Three flutes provide clean chip evacuation during forward-direction cutting. Machinists and tool-and-die professionals install this tool in drill presses, milling machines, and CNC machining centers where socket-head cap screw seating is required.

This counterbore is sized specifically for 3/4 inch socket-head cap screws, producing the correct seat depth and diameter to allow the fastener head to sit flush or below the workpiece surface. It is suited for use in alloy tool steel, carbon steel, and cast iron. Typical applications include fixture building, machine component assembly, and structural fabrication work where fastener heads must be recessed for clearance or a clean surface profile. The standard pilot configuration makes it a direct fit for most conventional counterboring setups without requiring a separate pilot pin.

Key Features

• 1-1/32 inch counterbore diameter sized for 3/4 inch socket-head cap screws
• 25/32 inch standard pilot maintains concentricity with the through-hole
• High-speed steel construction handles alloy tool steel, carbon steel, and cast iron
• 3-flute geometry supports efficient chip evacuation in forward cutting direction
• 1 inch straight-cylindrical shank for secure chuck or collet retention
• Bright, uncoated finish suitable for use with cutting fluids

Compatibility

Designed for use with 3/4 inch socket-head cap screws. Compatible work materials include alloy tool steel, carbon steel, and cast iron. Fits standard drill press, milling machine, or machining center spindles accepting a 1 inch straight shank.

Installation Notes

This tool is installed and operated by machinists or toolmakers following standard machine shop practices. Ensure the spindle and workpiece are fully secured and all guards are in place before operation. Always use an appropriate cutting fluid for the workpiece material to extend tool life and improve surface finish. Inspect the pilot and cutting edges for wear or damage before each use and replace the tool if chipping or deformation is present.