Hertel MR34-0783.438 Chucking Reamer No. 47 Carbide

Product Description

The HERTEL MR34-0783.438 is a solid carbide chucking reamer designed to produce precise, finished bores in metalworking applications. Ground to a No. 47 wire size (0.0785 inches decimal diameter), this reamer features a four-flute spiral flute geometry with a left-hand spiral and right-hand cut configuration. The left-hand spiral pushes chips forward, reducing the risk of chip packing in blind or through holes. At 1.9685 inches overall length with an 11 mm (0.433 inch) flute length, it is suited for use in CNC machining centers, drill presses, and manual lathes with a collet or chuck. It ships uncoated (bright finish) for immediate use.

This reamer is used in precision hole-finishing operations across job shops, production machining, and toolroom environments. It is appropriate for ferrous and non-ferrous materials where tight bore tolerances are required. The straight shank mounts directly into standard collet chucks or drill chucks. Typical applications include finishing drilled or bored holes to close dimensional tolerances where surface finish and size control are critical. Installation and use are performed by machinists and tool-and-die professionals working to print-specified hole tolerances.

Key Features

• Solid carbide construction provides rigidity and wear resistance in hard or abrasive materials
• No. 47 wire size, 0.0785 inches decimal diameter with a tolerance of 0.0000 to +0.0003 mm
• Left-hand spiral, right-hand cut geometry promotes forward chip evacuation
• Four-flute design balances cutting forces and improves bore finish
• Bright, uncoated finish — ready to run without additional prep
• Straight shank for compatibility with standard collet and drill chuck toolholders

Compatibility

Designed as an OEM-style solid carbide chucking reamer for use in standard straight-shank collet chucks and drill chucks on CNC machining centers, drill presses, and manual lathes requiring a No. 47 wire size bore finish.

Installation Notes

This reamer is installed and operated by qualified machinists. Ensure the machine spindle and toolholder are fully de-energized and the spindle is stopped before mounting or removing the reamer. Secure the straight shank firmly in a matched collet or chuck to minimize runout, as excessive runout will degrade bore tolerance and tool life. Apply an appropriate cutting fluid for the workpiece material — dry running solid carbide reamers in steel significantly reduces tool life.