Sandvik Coromant 7861066 TCMT221-PM 4425 Turning Insert

Product Description

The SANDVIK COROMANT 7861066 is a TCMT-style triangular turning insert from the CoroTurn 107 series, designed for external turning operations on CNC lathes and turning centers. It features a solid carbide substrate with a CVD-applied multilayer coating of Al2O3, TiCN, and TiN, producing a wear-resistant edge suited for medium to finishing cuts. The insert has a 60-degree included angle, a 0.4 mm corner radius, a 1/4-inch inscribed circle, and a 1/8-inch thickness. The PM chip breaker geometry controls chip flow across a wide range of feed rates and depths of cut. Installed by machinists and CNC operators in production and job-shop environments.

This insert is engineered primarily for turning steel (ISO material group P) and cast iron (ISO material group K). The CoroTurn 107 series is suited for external profiling, facing, and light finishing passes where consistent surface finish and dimensional accuracy are required. The neutral hand designation means the insert fits both right-hand and left-hand toolholders configured for TCMT geometry. The ISO code for this insert is TCMT 11 03 04-PM 4425, also catalogued under TCMT 221-PM 4425.

Key Features

• CVD multilayer coating: Al2O3, TiCN, and TiN for extended wear resistance and heat management
• 60-degree triangular insert shape with 3 usable cutting edges per insert
• 0.4 mm corner radius for a balance of edge strength and surface finish capability
• PM chip breaker geometry suited for steel and cast iron turning applications
• Neutral hand insert compatible with clamp and screw holding methods
• Manufacturer grade 4425 optimized for ISO P (steel) primary and ISO K (cast iron) secondary workpiece materials

Compatibility

Compatible with TCMT-style toolholders that accept a 1/4-inch inscribed circle triangular insert with clamp or screw holding. The ISO industry standard number TCMT 11 03 04-PM 4425 can be used to cross-reference compatible toolholder systems. Designed for use in the CoroTurn 107 series tooling platform.

Installation Notes

Installation is performed by machinists or CNC setup technicians. Ensure the machine spindle is fully stopped and the turret is locked before seating or indexing the insert. Use the correct torque wrench and screw driver specified for the toolholder to secure the clamp or mounting screw without over-tightening, which can crack the carbide substrate. Inspect the insert pocket and seating surfaces for chips or debris before installing a fresh cutting edge.