Hertel H59869941 Indexable Boring Bar 0.438 in Min Bore

Product Description

The HERTEL H59869941 is a steel indexable boring bar designed for precision internal turning and boring operations on metalworking lathes and turning centers. Built to the HBBQ toolholder style, it accepts TPC-style inserts secured by a screw clamp system for quick, repeatable insert changes without removing the bar from the holder. The bar features a 1/2 inch shank diameter, a minimum bore diameter of 0.438 inches, a maximum bore depth of 1.875 inches, and an overall length of 3.75 inches. Coolant-through capability allows cutting fluid delivery close to the insert tip, supporting chip evacuation and tool life in deep bore applications. This is a right-hand cut holder.

This boring bar is suited for small-diameter internal boring, back-facing, and chamfering operations in job shop and production machining environments. Its compact minimum bore diameter of 0.438 inches makes it appropriate for tight-bore workpieces in steel, cast iron, and similar materials. The screw-clamping insert retention method is standard practice in CNC lathe tooling, allowing machinists to index or replace worn inserts quickly at the machine. The 1/2 inch shank fits standard boring bar holders and quick-change toolpost systems commonly found on CNC and manual turning equipment.

Key Features

• HBBQ toolholder style with screw-clamp insert retention for positive insert seating
• Accepts TPC-style indexable inserts for broad grade and geometry availability
• Coolant-through design delivers fluid directly to the cutting zone
• Right-hand cut orientation for standard OD and ID turning setups
• Steel construction provides rigidity and damping in small-bore applications
• Minimum bore diameter of 0.438 inches suits tight-bore workpiece requirements

Compatibility

Designed for use with TPC-style indexable inserts. The 1/2 inch shank fits standard boring bar holders and quick-change toolpost systems on CNC and manual lathes. Insert selection will vary by grade, geometry, and workpiece material.

Installation Notes

Installation is performed by qualified machinists following standard lathe tooling setup procedures. Power down and lock out the machine before mounting or removing the boring bar from the toolholder. Ensure the shank is fully seated and clamped to the specified overhang to minimize vibration and deflection in small-bore cuts. Follow the insert manufacturer torque guidance when tightening the clamp screw, and verify runout before taking the first pass.