Hertel H59869057 Indexable Boring Bar 5/16 Inch Shank

Product Description

The HERTEL H59869057 is a steel indexable boring bar designed for internal turning and bore finishing operations on CNC lathes and manual turning centers. Built to the HBBF toolholder style, this bar accepts TD-series inserts secured by a screw-clamp holding method, providing repeatable positioning and quick index changes at the cutting edge. With a 0.36-inch minimum bore diameter and a 5/16-inch shank diameter, it is suited for small-diameter bores where rigidity and clearance are both critical factors. The 4-inch overall length and coolant-through capability support chip evacuation and tool life in production environments.

This boring bar is intended for use in small-bore internal machining applications on lathes and turning centers in metalworking shops, tool rooms, and production facilities. It handles bores up to 1.25 inches in depth, making it appropriate for short to medium-depth finish and semi-finish boring passes in steel, cast iron, and similar workpiece materials. Licensed machinists and CNC operators in job shop and production settings are the primary users.

Key Features

• Minimum bore diameter of 0.36 inches for access to small internal diameters
• Maximum bore depth of 1.25 inches (1-1/4 inches) for short to medium-depth bores
• HBBF toolholder style with screw-clamp insert retention for secure, repeatable clamping
• Coolant-through design aids chip removal and extends cutting edge life
• 5/16-inch shank diameter for compatibility with standard boring bar holders and turrets
• Steel tool body construction for strength and durability in turning applications

Compatibility

Designed to accept TD-series indexable inserts. Fits standard boring bar holders and turret pockets sized for a 5/16-inch round shank. Verify insert geometry and grade selection against the workpiece material before use.

Installation Notes

Installation is performed by qualified machinists or CNC tooling technicians. Ensure the machine spindle is fully stopped and the turret or toolpost is locked before mounting or removing the bar. Confirm shank seating depth and overhang do not exceed the toolholder manufacturer's recommended extension-to-diameter ratio to maintain rigidity. Torque the insert-clamping screw to the insert manufacturer's specification using the appropriate torx or hex key supplied with the insert grade.