Sandvik Coromant 5757909 Threading Insert Corothread 266

Product Description

The SANDVIK COROMANT 5757909 is a solid carbide threading insert designed for internal thread cutting operations. Part of the CoroThread 266 series, this insert features a left-hand orientation and is manufactured to cut Metric 60-degree thread forms with an internal pitch of 1.25 mm. The insert carries manufacturer grade 1125 with a PVD coating process, which supports wear resistance and edge integrity during threading. At 3.97 mm thick and insert size 16, it fits CoroThread 266 toolholders configured for left-hand internal threading. Licensed machinists and CNC operators working in metalworking and precision machining environments install this insert type.

This insert is suited for internal threading applications on CNC lathes and turning centers where metric thread standards are required. The left-hand configuration makes it appropriate for reverse-thread applications or left-hand spindle setups. The chipbreaker designation A indicates a specific geometry suited for controlled chip formation during threading passes. It is used in production and job-shop environments where consistent metric thread quality is required on internal bores.

Key Features

• Solid carbide construction with PVD coating for extended tool life
• Metric 60-degree thread standard for internal thread cutting
• Left-hand insert orientation for reverse-thread and left-hand spindle applications
• 1.25 mm internal pitch for standard metric threading
• Chipbreaker style A for controlled chip evacuation
• Insert size 16, compatible with CoroThread 266 series toolholders

Compatibility

Designed for use with SANDVIK COROMANT CoroThread 266 series toolholders configured for left-hand internal threading inserts at insert size 16.

Installation Notes

Installation and replacement of threading inserts should be performed by a qualified machinist or CNC tooling technician with the machine in a safe, powered-down or tool-change state. Use the appropriate torque wrench and insert key specified for the CoroThread 266 toolholder to seat the insert correctly. Inspect the toolholder pocket for wear or debris before seating a new insert. Do not exceed the recommended depth of cut or feed rate for the workpiece material and thread pitch.