Hertel 72308216 Chucking Reamer Size 21 Cobalt Steel

Product Description

The HERTEL 72308216 is a straight-flute chucking reamer designed to finish-ream holes to a precise 0.1590-inch diameter, corresponding to wire size 21. Built from cobalt steel with a bright, uncoated finish, this reamer delivers the hardness and heat resistance required for accurate sizing in ferrous and harder workpiece materials. It features six right-hand cutting flutes and a straight-cylindrical shank that seats securely in standard drill chucks or collet-style holders. Overall length is 4.0 inches with a 1.125-inch flute length. Machinists and toolroom technicians rely on this geometry for finish passes that bring bored or drilled holes to tight dimensional tolerance.

This chucking reamer is suited for use in CNC machining centers, manual mills, and drill presses where a controlled finish pass is needed after drilling. Wire-gauge reamers in the 0.1590-inch range are commonly used in precision hole finishing for jig work, fixture building, and production machining of small-diameter bores. The straight-cylindrical shank accommodates standard collet chucks and keyless drill chucks without adapters. It is intended for right-hand rotation with a slow, steady feed rate and adequate cutting fluid to preserve edge life.

Key Features

• 0.1590-inch reamer diameter (wire size 21) for precise hole finishing
• Cobalt steel construction for improved hardness and heat resistance over standard HSS
• Six straight right-hand flutes for smooth, controlled material removal
• Bright, uncoated finish suitable for general-purpose reaming applications
• Straight-cylindrical shank fits standard drill chucks and collet holders without adapters
• Not configured as a dowel pin reamer or over/under size reamer

Compatibility

Designed as a standard chucking reamer for use in any machine tool spindle accepting a straight-cylindrical shank in the corresponding diameter range.

Installation Notes

This tool is installed by a machinist or toolroom technician in a drill chuck or precision collet holder. Power down and lock out the machine spindle before changing or inspecting tooling. Apply cutting fluid or cutting oil during reaming to extend flute life and improve finish quality. Do not use this reamer as a drilling tool; always pre-drill or bore the hole to near-final size before reaming.