Kennametal 4121715 VNMG332MS KCU25 Carbide Turning Insert

Product Description

The KENNAMETAL 4121715 is a VNMG332MS style solid carbide turning insert in the KCU25 grade, designed for high-performance metal cutting on CNC lathes and turning centers. The insert features a 35-degree diamond shape (V-shape code), a 3/8-inch inscribed circle, and a 1/32-inch corner radius. The AlTiN coating is applied via PVD process, providing strong thermal and oxidation resistance suited to interrupted cuts and tough workpiece materials. The MS chip breaker geometry, combined with a honed cutting edge and negative rake angle of 13 degrees, controls chip flow and reduces built-up edge when turning steel, stainless steel, superalloys, and titanium. Licensed HVAC techs install this type of equipment. This insert is installed by machinists and CNC operators in production and job-shop environments.

The 4121715 is engineered for turning, facing, boring, back turning, and back boring operations on a wide range of workpiece materials coded P, M, and S under ISO classification. The MS chip breaker is specifically developed for medium-finish to roughing passes on steel and stainless steel, and it handles the work-hardening behavior of superalloys and titanium effectively. The insert seats in a KENLOC-style toolholder using a clamp-and-pin holding method, which ensures consistent edge indexing across all four cutting edges. Maximum depth of cut reaches 0.4354 inches, and the insert length is 1.3076 inches.

Key Features

• AlTiN PVD coating for thermal resistance and extended tool life in ferrous and exotic alloy cutting
• 35-degree diamond (VNMG) geometry with negative rake for strong, supported cutting edges
• MS chip breaker controls chip flow across turning, facing, boring, back turning, and back boring operations
• Four usable cutting edges per insert — neutral hand orientation for flexible toolholder use
• Clamp and pin holding method provides rigid insert location in KENLOC-compatible toolholders
• Honed cutting edge style reduces microchipping and supports consistent surface finish

Compatibility

Designed for use in KENLOC-style toolholders that accept VNMG 332 inserts with clamp-and-pin retention. Compatible with turning centers and CNC lathes running steel (ISO P), stainless steel (ISO M), superalloys, and titanium (ISO S) workpiece materials. Conforms to ANSI and ISO standards; ISO code VNMG160408MS.

Installation Notes

Installation is performed by a qualified machinist or CNC tooling technician. Ensure the machine spindle is fully stopped and the turret is locked before indexing or replacing inserts. Seat the insert firmly against the toolholder pocket locating surfaces before engaging the clamp-and-pin mechanism — partial seating causes premature edge failure. Inspect the insert pocket and clamp hardware for wear or debris before each insert change.