Hertel H59870402 Indexable Boring Bar 0.855 in Min Bore

Product Description

The HERTEL H59870402 is a steel-body indexable boring bar designed for internal diameter machining on lathes and boring mills. Built to the HBBS toolholder style with a 3/4 inch shank diameter and 4 inch overall length, it accepts TD and TP series indexable inserts secured by a screw-style clamping method. The minimum bore diameter is 0.855 inches with a maximum bore depth of 2.5 inches. Coolant-through capability supports chip evacuation and tool life in production environments. This bar is intended for right-hand cutting operations and is used by machinists and toolroom personnel in both job-shop and production settings.

This boring bar is suited for internal turning and bore finishing operations on CNC lathes, manual lathes, and horizontal boring mills. The 0.855 inch minimum bore diameter makes it appropriate for small-to-medium bore applications in steel, cast iron, and similar machinable alloys. The screw-style insert retention provides repeatable insert indexing, which supports consistent diameter control across production runs. It is a single-application tool with no multi-use designation, meaning it is configured specifically for boring rather than combined operations.

Key Features

• Minimum bore diameter of 0.855 inches suits small-bore internal turning applications
• Maximum bore depth of 2.5 inches accommodates standard through and blind bore work
• 3/4 inch shank diameter for rigid toolholder mounting
• Screw-style insert clamping ensures repeatable insert indexing
• Compatible with TD and TP series indexable inserts
• Coolant-through design supports chip control and extended insert life
• Right-hand cut orientation for standard lathe and boring mill setups

Compatibility

Designed for use with TD and TP series indexable inserts. Verify insert geometry and grade selection against workpiece material and cutting parameters before installation.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician. Secure the shank fully in the toolholder or boring head to the manufacturer-recommended grip length before commencing cuts. Confirm insert seating and screw torque per the insert manufacturer guidelines before engaging the workpiece. Ensure the machine spindle is fully stopped and the machine is in a safe state before changing inserts or adjusting the bar.