Accupro B290750R Corner Radius Boring Bar Solid Carbide

Product Description

The ACCUPRO B290750R is a corner radius boring bar designed for precision internal turning and boring operations on CNC and manual lathes. Machined from submicron solid carbide, it delivers the rigidity and wear resistance needed for tight-tolerance work in hardened steels, cast iron, and non-ferrous alloys. The right-hand cut geometry suits standard spindle rotation. Key dimensions include a 5/16-inch shank diameter, 2.5-inch overall length, 0.29-inch minimum bore diameter, and a maximum bore depth of 0.75 inches. The corner radius ranges from 0.005 to 0.008 inches, allowing for controlled blending at the bore floor without sharp stress risers.

This boring bar is suited for small-diameter internal boring applications in job shops, production machining, and tool rooms. It is particularly useful when a defined corner radius is required at the base of a blind bore to meet part print requirements. The bright finish coating keeps the bar free of built-up edge in light-to-medium cutting passes. Machinists and CNC programmers working on precision components in aerospace, mold and die, and general metalworking will find this bar appropriate for applications where dimensional accuracy in small-bore geometry is critical.

Key Features

• Submicron solid carbide construction for high rigidity and extended tool life
• Corner radius range of 0.005 to 0.008 inches for controlled bore-floor geometry
• Right-hand cut orientation for standard spindle rotation on most lathes
• 0.29-inch minimum bore diameter supports small-hole internal turning
• Bright finish coating resists built-up edge in non-ferrous and ferrous materials
• Compact 2.5-inch overall length suited for close-clearance setups

Compatibility

Designed as a direct-fit boring bar for any lathe or machining center toolholder accepting a 5/16-inch round shank, with a maximum bore depth of 0.75 inches.

Installation Notes

A qualified machinist should install and set this boring bar in a rigid, properly sized toolholder to minimize overhang and chatter. Secure all toolholder fasteners fully before initiating a cut, and verify shank engagement depth meets toolholder manufacturer recommendations. Inspect the cutting edge under magnification before use to confirm the carbide is free of chips or cracks. Follow your machine's lockout and energy-isolation procedure before changing or adjusting tooling.