Hertel 79891057 Chucking Reamer Letter H Solid Carbide

Product Description

The HERTEL 79891057 is a solid carbide chucking reamer sized to Letter H (0.2660 inches diameter) for precision hole finishing in metalworking applications. Built with six straight flutes and a bright, uncoated finish, it delivers consistent, accurate results in materials where tight tolerances are required. The straight-cylindrical shank seats directly in drill chucks or collet holders without adapters. With an overall length of 3.25 inches and a flute length of 1.125 inches, this reamer is suited for short-reach finishing passes in production and toolroom environments. Diameter tolerance is held to 0.0000 to 0.0003 inches, making it appropriate where close-fit holes are specified.

This chucking reamer is used in machine shop, toolroom, and production floor applications where a Letter H hole finish is required. It is intended for use in CNC machining centers, turret lathes, and drill presses operating with right-hand cutting rotation. The solid carbide construction makes it well-suited for harder workpiece materials and applications requiring longer tool life compared to high-speed steel alternatives. It is sold individually and is appropriate for single-piece and low-volume production runs alike.

Key Features

• Letter H diameter (0.2660 inches) with tolerance held to 0.0000 to 0.0003 inches
• Solid carbide construction for extended tool life in harder materials
• Six straight flutes with bright, uncoated finish for clean chip evacuation
• Straight-cylindrical shank for direct chuck or collet mounting
• Right-hand cutting direction compatible with standard machine rotation
• Compact 3.25-inch overall length for close-quarter finishing operations

Compatibility

Designed as an OEM-style solid carbide chucking reamer for use in standard drill chucks and collet systems accepting a straight-cylindrical shank in the Letter H diameter range (0.2500 to 0.2999 inches).

Installation Notes

This reamer is installed and operated by a machinist or toolroom technician in a powered machine tool. Ensure the machine spindle and workpiece are fully secured before engaging the reamer. Use appropriate cutting fluid for the workpiece material to extend tool life and maintain surface finish quality. Solid carbide tooling is brittle — avoid side-loading or interrupted cuts that can cause chipping or fracture.