Osg 300-3390 Chucking Reamer Letter R Solid Carbide

Product Description

The OSG 300-3390 is a solid carbide chucking reamer designed for precision hole finishing in general machining applications. It carries a Letter R designation, corresponding to a decimal diameter of 0.3390 inches, and holds a tight tolerance of +0.0001 to +0.0005 inches, making it suitable for close-tolerance bore work. The straight flute geometry and right-hand cutting direction are well matched to through-hole and blind-hole reaming on CNC machining centers, manual mills, and drill presses. Machinists and tool-and-die professionals are the primary users of this type of reamer.

This reamer fits into general-purpose production and job-shop environments where repeatable bore diameters are required. Its bright, uncoated finish makes it appropriate for use on a wide range of workpiece materials under standard cutting conditions. The straight cylindrical shank seats directly in a collet chuck, drill chuck, or ER-style holder without additional adapters. It belongs to the OSG 300D series, which covers standard carbide reamers for general machining applications. No coolant-through capability is incorporated, so external coolant or cutting fluid applied at the entry point is the standard practice.

Key Features

• Letter R diameter (0.3390 inches) with tolerance of +0.0001 to +0.0005 inches for close-tolerance bore finishing
• Solid carbide construction provides rigidity and wear resistance compared to high-speed steel alternatives
• 6-flute straight geometry for smooth cutting action and consistent surface finish
• Bright/uncoated finish suitable for general machining across common workpiece materials
• Straight cylindrical shank for direct mounting in collet chucks or ER-style toolholders
• No coolant-through passages — compatible with conventional external coolant delivery

Compatibility

Designed as a general-purpose OEM-style chucking reamer from the OSG 300D series, suited for standard machining center spindles and manual machine tools that accept a straight cylindrical shank reamer of this diameter range.

Installation Notes

A licensed machinist or qualified tooling technician should install and run this reamer. Secure the straight shank in a properly sized collet or chuck to minimize runout before cutting. Ensure the machine spindle is fully stopped and the tool is locked before making any chuck adjustments. Apply appropriate cutting fluid externally at the reaming entry point, as this tool does not support internal coolant delivery.