Kennametal 4033830 Threading Insert NA4R4 KCU25 Carbide Altin

Product Description

The KENNAMETAL 4033830 is a carbide threading insert in the Top Notch series, designed for cutting Acme threads at 4 threads per inch (TPI) with a 29-degree included angle. The insert carries a KCU25 manufacturer grade and features an AlTiN finish applied via PVD coating, which improves wear resistance and tool life in demanding threading operations. At 0.2551 inches thick with a cutting tip width of 0.0875 inches and a corner radius of 0.0050 inches, this right-hand insert handles both internal and external thread forms. It is installed by machinists and CNC operators using compatible Top Notch toolholders.

This insert is suited for threading operations on lathes and CNC turning centers where Acme thread profiles are required. Acme threads are common in lead screws, power transmission components, and linear actuation hardware. The right-hand orientation and 4 TPI pitch make this insert applicable to standard Acme fastener and mechanical drive applications in both production and job-shop environments. The AlTiN PVD coating supports use in a range of workpiece materials where heat resistance and edge retention are priorities.

Key Features

• KCU25 carbide grade with AlTiN PVD coating for extended wear resistance
• 29-degree included angle for Acme thread profile, 4 TPI internal and external
• Right-hand cutting orientation, NA insert style
• Top Notch series insert for use with compatible Top Notch toolholders
• Corner radius of 0.0050 inches for precise thread root geometry
• Cutting tip width of 0.0875 inches (2.22 mm)

Compatibility

Designed for use with Top Notch series toolholders that accept NA4 style inserts. Verify toolholder insert seat specifications before installation. No specific model compatibility data was provided beyond the Top Notch series designation.

Installation Notes

Installation should be performed by a qualified machinist or CNC technician. Power down and lock out the machine before seating or replacing the insert. Use the correct torque and clamping hardware specified for the Top Notch toolholder being used. Inspect the insert seat for chips or debris before installation to prevent seating errors and premature insert failure.