Kennametal 4109950 Threading Insert NT4LK KCU25 Carbide

Product Description

The KENNAMETAL 4109950 is a carbide threading insert in the Top Notch series, designed for both internal and external thread-cutting operations on CNC lathes and turning centers. Coated with AlTiN via a PVD process, it delivers excellent wear resistance and thermal stability in demanding threading applications. The insert is configured in a left-hand orientation with a partial profile 60-degree thread form and an included angle of 60 degrees. External pitch range spans 1.25 to 6.25 mm (4 to 20 TPI), while internal pitch range covers 2.00 to 6.25 mm (4 to 12 TPI). Machinists and CNC operators working in metalworking shops and production environments install this insert for precision threading work.

This insert is suited for threading applications requiring a left-hand partial profile 60-degree form in both internal and external configurations. The Top Notch series tooling system is a common platform used across job shops and production machining environments. The AlTiN coating makes it appropriate for dry or semi-dry cutting conditions and high-temperature materials. It is compatible with the NT4LK insert style and KCU25 grade tooling holders designed for the Top Notch system.

Key Features

• Carbide substrate with AlTiN finish applied via PVD coating process for extended tool life
• Left-hand insert orientation for left-hand thread-cutting operations
• Partial profile 60-degree thread form handles both internal and external threading in a single insert style
• External pitch range: 1.25 to 6.25 mm (4 to 20 TPI)
• Internal pitch range: 2.00 to 6.25 mm (4 to 12 TPI)
• Corner radius of 0.17 mm (0.0067 inches) for consistent thread form accuracy

Compatibility

Designed for use with Top Notch series threading toolholders accepting NT4LK style inserts. Compatible with KCU25 grade tooling setups for partial profile 60-degree internal and external threading operations.

Installation Notes

Installation is performed by a CNC machinist or toolroom technician. Power down and lock out the machine before changing inserts. Seat the insert firmly in the Top Notch toolholder pocket and torque the clamp screw per the toolholder manufacturer's specification. Inspect the insert seating surface and clamp for debris or wear before each installation to avoid chatter or thread form error.