Hertel 79890430 Chucking Reamer No. 4 Solid Carbide

Product Description

The HERTEL 79890430 is a solid carbide chucking reamer designed for precision hole finishing in metal fabrication and machining applications. Built to a No. 4 wire size with a decimal diameter of 0.2090 inches, this reamer holds a tight tolerance of 0.0000 to 0.0002 inches, making it well suited for close-tolerance bores that require a clean, accurate finish. The straight flute geometry and right-hand cut provide consistent chip clearance in through-hole applications. The straight cylindrical shank is compatible with standard drill chucks and collet holders. At 3.0 inches overall length with a 1.0 inch flute length, this tool fits common CNC machining centers and manual drill presses.

This chucking reamer is used in machine shops, tool rooms, and production environments where precise hole sizing is required after drilling. It is appropriate for ferrous and non-ferrous materials where solid carbide tooling provides the rigidity and wear resistance needed to maintain diameter tolerance across repeated cycles. The bright, uncoated finish suits applications where coating interaction with the workpiece material is a concern. Licensed machinists and CNC operators are the primary users of this tool.

Key Features

• No. 4 wire size with 0.2090 inch decimal diameter for precise hole finishing
• Solid carbide construction provides high rigidity and extended tool life
• Straight flute geometry supports clean chip evacuation in through-hole applications
• Right-hand cutting direction for standard spindle rotation
• Tight reamer diameter tolerance of 0.0000 to 0.0002 inches
• Bright, uncoated finish compatible with a wide range of workpiece materials

Compatibility

Designed as an OEM-style chucking reamer for use in standard drill chucks and collet holders accepting a straight cylindrical shank. No specific machine or system compatibility was provided by the manufacturer for this part.

Installation Notes

This reamer is installed and operated by qualified machinists using standard drill presses, CNC machining centers, or manual milling machines equipped with a compatible chuck or collet. Ensure the workpiece is securely fixtured and the spindle is brought to the appropriate speed for the material being reamed before engaging the tool. The hole should be pre-drilled to a suitable undersize before reaming to achieve the specified tolerance. Do not use this tool for applications that exceed its rated flute length, and never force the reamer through a hole that has not been properly piloted.