Iscar 5508126 TCMT21SM IC8250 Carbide Turning Insert

Product Description

The ISCAR 5508126 is a solid carbide turning insert in the TCMT21SM style, part of the Isoturn series. It carries a multilayer PVD coating of TiCN, Al2O3, and TiN under manufacturer grade IC8250, delivering wear resistance and thermal protection during continuous and interrupted turning operations. The insert features a triangular shape with a 60-degree included angle, a 1/4-inch inscribed circle, a 3/32-inch thickness, and a 1/64-inch corner radius. With a positive rake geometry and SM chip breaker, it is designed to control chip flow and reduce cutting forces. Licensed HVAC technicians do not install this part — it is specified and installed by machinists and CNC turning center operators in metal-cutting environments.

This insert is suited for turning operations on stainless steel and carbon or alloy steel workpieces, corresponding to ISO material codes M and P. The SM chip breaker geometry performs well in medium finishing and light roughing passes. Maximum depth of cut is 3.00 mm (0.118 inches). The screw-clamping holding method is standard for TCMT-style toolholders used in CNC lathes and manual turning centers across job shops and production environments.

Key Features

• Solid carbide substrate with PVD-applied TiCN, Al2O3, and TiN multilayer coating under IC8250 grade
• Triangular insert shape with 60-degree included angle and positive rake for reduced cutting forces
• SM chip breaker geometry optimized for stainless steel and steel turning applications
• 1/64-inch corner radius for controlled surface finish in finishing and semi-finishing passes
• Screw-mounted (TCMT style) for secure seating in compatible indexable toolholders
• Compliant with ISO 13399 cutting tool data representation standard

Compatibility

Designed as an OEM-style indexable replacement for TCMT-style screw-clamp turning toolholders compatible with a 1/4-inch inscribed circle triangular insert. Intended for use with stainless steel and steel workpiece materials per ISO material codes M and P.

Installation Notes

Insert seating and indexing should be performed by a qualified machinist with the machine spindle fully stopped and the toolholder secured in the turret. Use the appropriate Torx or hex key to tighten the clamping screw — consult the toolholder manufacturer documentation for fastener specifications. Inspect the insert pocket for chips or debris before seating a new edge. Follow shop safety procedures and applicable ANSI or ISO tooling standards when indexing or replacing inserts.