Hertel 72309024 Chucking Reamer Letter B Cobalt Steel

Product Description

The HERTEL 72309024 is a straight-flute chucking reamer designed for precision hole finishing in metal fabrication and machining applications. It is sized to Letter B, with a decimal diameter of 0.2380 inches, making it suitable for close-tolerance bores that require a clean, accurate finish after drilling. Constructed from cobalt steel with a bright, uncoated finish, it delivers hardness and heat resistance appropriate for ferrous and harder workpiece materials. The reamer features 6 straight flutes and a right-hand cutting direction, with a straight-cylindrical shank for direct chuck mounting in CNC machines, lathes, or drill presses.

This reamer is used in machine shops, production environments, and tool rooms where reamed holes must meet tight dimensional tolerances. The 6-inch overall length and 1.5-inch flute length suit standard depth finishing passes on through-holes and moderate blind-hole applications. It is installed and operated by machinists and tool-and-die professionals using standard chucking setups. The cobalt steel construction makes it a practical choice where high-speed steel reamers wear prematurely due to elevated cutting temperatures or abrasive materials.

Key Features

• Letter B diameter (0.2380 inches) for precise hole sizing
• Cobalt steel construction for improved heat and wear resistance over standard HSS
• 6 straight flutes with right-hand cutting direction
• Bright, uncoated finish — no coating buildup to affect tolerance
• Straight-cylindrical shank for secure chuck mounting
• 6-inch overall length with 1.5-inch flute length for standard-depth finishing

Compatibility

Designed as a direct-chuck chucking reamer for use in lathes, CNC machining centers, and drill presses equipped with a straight-bore chuck capable of accepting a straight-cylindrical shank at this diameter class.

Installation Notes

Chucking reamers are installed and operated by qualified machinists. Power down and lock out the machine before mounting or removing the reamer from the chuck. Ensure the shank is fully seated and the chuck is tightened evenly before running. Use appropriate cutting fluid for the workpiece material to maximize tool life and surface finish quality. Do not use a chucking reamer to remove excessive stock — always pre-drill to within accepted reaming allowance before finishing.