Iscar 6403942 Indexable Boring Bar 3.99mm Shank

Product Description

The ISCAR 6403942 is an indexable boring bar designed for small-diameter internal turning and boring operations on CNC lathes and machining centers. Built around the PICCO-R002.0050-5IC908 designation, this tool accepts indexable inserts for repeatable cutting performance without full tool replacement. The shank diameter measures 3.99 mm and the overall length is 19 mm (0.748 inches), making it suited for tight-bore and micro-boring applications. Machinists and toolroom technicians working with precision small-hole finishing operations are the primary users of this tool.

This boring bar fits into applications requiring accurate internal diameter work at small bore sizes. Its compact overall length of 19 mm and narrow 3.99 mm shank allow it to reach into restricted workpiece geometries where larger tooling cannot fit. Typical use cases include finish boring on Swiss-type screw machines, small CNC lathes, and multi-axis machining centers. It is appropriate for both production and prototype work where insert indexability reduces downtime and maintains consistent cutting geometry across multiple parts.

Key Features

• Indexable insert design allows insert replacement without removing the bar from the holder
• 3.99 mm shank diameter enables access to small and restricted bore geometries
• 19 mm overall length provides rigidity in compact tooling setups
• PICCO-R002.0050-5IC908 designation identifies compatible insert family for direct reordering
• Lightweight at 0.5 pounds, minimizing spindle load in small-machine applications

Compatibility

Designed as an OEM-style indexable boring bar compatible with tooling systems that accept 3.99 mm shank boring tools and PICCO-series indexable inserts.

Installation Notes

Installation and setup should be performed by a qualified machinist or toolroom technician. Ensure the machine spindle is fully stopped and the control is in an e-stop or locked-out state before loading or changing tooling. Secure the shank firmly in the appropriate boring bar holder or collet system, confirming runout is within the tolerance required for the application. Follow the insert manufacturer guidelines for insert seating and clamping torque to avoid insert movement during cutting.