Sandvik Coromant 5857543 Laydown Threading Insert 8 Tpi

Product Description

The SANDVIK COROMANT 5857543 is a solid carbide laydown threading insert designed for external Acme thread cutting on CNC lathes and turning centers. Part of the CoroThread 266 series, this insert carries a PVD-applied TiCrAlN/TiN finish that extends cutting edge life in demanding threading operations. It is configured for right-hand external threading at 8 threads per inch (TPI) with a 60-degree included angle and a single tooth per side. The inscribed circle measures 3/8 inches and the insert thickness is 5/32 inches (0.1563 inches decimal). Machining professionals and CNC operators use this insert where precision Acme thread profiles are required on external workpiece diameters.

This insert is suited for threading operations in general machining, power transmission component manufacturing, and motion-control hardware production where Acme thread forms are specified. The F chipbreaker geometry is intended for controlled chip evacuation during single-point threading passes on turning equipment. The CoroThread 266 platform is a common choice in job shops and production environments that require consistent thread form accuracy across multiple parts. Installation is performed by machinists and CNC technicians working with compatible 266-series toolholders.

Key Features

• Solid carbide substrate with PVD TiCrAlN/TiN coating for wear and heat resistance
• Right-hand external Acme thread profile at 8 TPI with 60-degree included angle
• F chipbreaker geometry for controlled chip management during threading passes
• Inscribed circle of 3/8 inches (9.53 mm) and thickness of 5/32 inches (3.97 mm)
• Single tooth per side for precise Acme thread form accuracy
• Part of the CoroThread 266 series for use with compatible 266-series toolholding systems

Compatibility

Designed for use with SANDVIK COROMANT CoroThread 266 series toolholders that accept the 266RG-16AC01F080E insert style and size code 16 configuration. Confirm toolholder bore diameter compatibility with the 4.40 mm (0.1732 inch) hole diameter before installation.

Installation Notes

This insert is installed and indexed by qualified machinists or CNC technicians. Ensure the machine spindle is fully stopped and the toolholder is secured before seating or replacing the insert. Use the appropriate torx or hex key specified by the toolholder manufacturer to achieve proper clamping without overtightening. Verify thread form accuracy with a thread gauge after the first pass before committing to full production runs.