Kennametal 3781278 Grooving Insert 3mm A4 KCU10

Product Description

The KENNAMETAL 3781278 is a solid carbide grooving insert designed for precision groove turning and parting operations on CNC lathes and turning centers. It carries the KCU10 manufacturer grade with a Physical Vapor Deposition (PVD)-applied AlTiN coating, which provides thermal resistance and extended tool life in demanding cutting conditions. The insert features a 3.00 mm cutting width, a maximum depth of cut of 2.90 mm, and a positive rake geometry with a GUP chip breaker. It is installed by machinists and CNC turning technicians working in metal-cutting production environments.

This insert is suited for grooving, recessing, and light parting operations in ferrous and non-ferrous materials where the KCU10 carbide grade and AlTiN finish provide reliable performance. The neutral hand orientation allows use in standard A4-series toolholders without a left- or right-hand restriction. The GUP chip breaker geometry is optimized for chip control across a range of feed rates and materials typically encountered in general-purpose turning. Material grades C3 and C4 indicate suitability for a broad range of workpiece materials in medium to fine finishing conditions.

Key Features

• 3.00 mm cutting width with a maximum depth of cut of 2.90 mm for controlled groove profiles
• KCU10 solid carbide grade with PVD AlTiN coating for heat and wear resistance
• Positive rake geometry with GUP chip breaker promotes efficient chip evacuation
• Corner radius of 0.20 mm (0.0079 inches) for tight groove-bottom tolerances
• Neutral hand — compatible with standard A4-series insert pockets without orientation restrictions
• Metric insert sizing in the A4 series for consistent toolholder fit

Compatibility

Designed for use in A4-series grooving toolholders that accept the A4G0300 insert style. Refer to the toolholder manufacturer specifications to confirm pocket geometry and clamping method compatibility before installation.

Installation Notes

This insert is seated and secured by a qualified machinist or CNC turning technician. Power down and lock out the machine spindle before changing inserts. Inspect the toolholder pocket for debris, damage, or wear before seating the insert, as a contaminated or worn pocket will affect seating accuracy and cutting performance. Follow the toolholder manufacturer torque specifications for the clamping screw — do not over-tighten, as carbide inserts are brittle and can crack under excessive clamp load.