Walter 7091933 VNMG160404-FM5 WSM20S Turning Insert

Product Description

The WALTER 7091933 is a solid carbide turning insert in the VNMG-FM5 series, designed for precision metal cutting in CNC lathe and turning center applications. It carries the ISO designation VNMG160404-FM5 WSM20S and features a PVD-applied TiCN, Al2O3, and Al multilayer coating under the proprietary WSM20S grade. The diamond-shaped (35-degree included angle) insert has a 0.4 mm corner radius, an inscribed circle of 0.375 inches (9.53 mm), and an insert length of 0.654 inches (16.61 mm). The FM5 chip breaker geometry and chamfered-and-honed cutting edge make this insert well suited for achieving controlled chip formation and surface finish in challenging materials.

This insert is engineered primarily for machining stainless steel and superalloys and titanium (ISO material codes M and S), with secondary suitability for general steel (ISO code P) at material grades M20, S20, and P20. It is a neutral-hand, negative-rake insert rated for turning, facing, boring, and back turning operations. The four available cutting edges and clamp-and-pin holding method make it a productive choice for production shops running tight-tolerance parts in aerospace, medical, and industrial applications.

Key Features

• WSM20S proprietary PVD grade with TiCN, Al2O3, and Al multilayer coating for heat and wear resistance in difficult-to-machine alloys
• FM5 chip breaker geometry optimized for controlled chip evacuation in stainless steel, superalloys, and titanium
• 35-degree diamond insert shape (V) with negative rake and chamfered-and-honed cutting edge for edge stability
• Four usable cutting edges per insert for extended tool life per unit
• Compatible with clamp and pin holding systems for secure seating under heavy cutting loads
• Meets ANSI and ISO standards; ISO code VNMG160404-FM5 WSM20S, industry standard number VNMG331-FM5 WSM20S

Compatibility

Designed for use in VNMG-style toolholders that accept a 35-degree diamond insert with a 3/8-inch inscribed circle, 3/16-inch thickness, and clamp-or-pin holding. Verify toolholder seat geometry and clamping style before installation.

Installation Notes

Installation should be performed by a qualified machinist or CNC setup technician with the machine in a full stop and lockout-tagout procedures applied before changing inserts. Seat the insert fully against the toolholder pocket and verify clamping torque per the toolholder manufacturer specification. Inspect the insert seat and clamping pin for wear or debris before each index. Do not operate the insert beyond its rated depth of cut or in materials outside its designated grade range, as this can cause premature edge failure or insert fracture.