Hertel 79891073 Chucking Reamer Letter J Solid Carbide

Product Description

The HERTEL 79891073 is a solid carbide chucking reamer sized to Letter J (0.2770 inches decimal diameter), designed to bring bored or drilled holes to precise final dimension. Built from solid carbide with a bright, uncoated finish, this reamer holds a diameter tolerance of 0.0000 to 0.0003 inches, making it suitable for applications where hole accuracy and surface finish are critical. Six straight flutes provide smooth, even cutting action on the right-hand cut. With an overall length of 3.25 inches and a flute length of 1.125 inches, it is sized for typical chucking operations in a drill press, lathe, or machining center. Licensed machinists and toolroom operators are the primary end users.

This reamer is used in precision metalworking applications requiring consistent, repeatable hole sizing in the 0.2500 to 0.2999 inch diameter range. It fits standard straight-cylindrical shank collets and chucks. Typical use cases include finish-reaming holes in ferrous and non-ferrous metals in both job-shop and production environments. It is not configured as a dowel-pin reamer or an over/under-size reamer.

Key Features

• Solid carbide construction for rigidity and wear resistance in demanding cut conditions
• Letter J diameter (0.2770 inches decimal) with tolerance of 0.0000 to 0.0003 inches
• Six straight flutes for smooth, consistent chip clearance
• Bright/uncoated finish — compatible with a broad range of cutting fluids and materials
• Right-hand cutting direction with straight-cylindrical shank for standard chuck mounting
• Overall length of 3.25 inches and flute length of 1.125 inches for compact chucking reach

Compatibility

Designed as a standard chucking reamer with a straight-cylindrical shank, compatible with collet chucks and drill chucks sized to accept the straight shank diameter in conventional drill presses, lathes, and CNC machining centers.

Installation Notes

Chucking reamers should be installed by qualified machinists following standard toolroom practices. Power down and lock out the machine before mounting or removing the tool from the chuck. Use the correct cutting fluid for the workpiece material to prolong tool life and maintain hole finish quality. Never force a reamer into an undersized pilot hole — pre-drill or bore to the appropriate starting diameter before reaming.