Tool-flo 0239040AC50E Acme Threading Insert 4 Tpi

Product Description

The TOOL-FLO 0239040AC50E is a solid carbide, on-edge threading insert designed for Acme thread forms on both external and internal applications. The insert features a neutral cutting direction and neutral rake geometry, making it suited for straight, non-handed setups. With a 0.5-inch inscribed circle (IC) and an AlTiN coating applied via PVD process, this insert delivers thermal resistance and surface hardness at the cutting edge. It runs at 4 threads per inch (TPI) on both external and internal passes. Machinists and toolroom operators use this insert in CNC turning and threading operations where Acme thread profiles are required on cast iron or steel workpieces.

This insert is intended for threading operations on ferrous materials, specifically cast iron (ISO K) and steel (ISO P). The on-edge series design positions the insert at the cutting edge for precise thread form engagement. Typical installations include power transmission components, lead screws, and other Acme-threaded parts machined on CNC lathes or threading-dedicated turning centers. The neutral hand designation allows the insert to be used in both directions of cut without requiring a dedicated right- or left-hand holder.

Key Features

• Solid carbide substrate with PVD-applied AlTiN coating for extended tool life on ferrous materials
• Acme thread form, external and internal, 4 TPI
• Neutral cutting direction and neutral rake for flexible setup in standard threading toolholders
• 0.5-inch inscribed circle (IC) for compatibility with standard on-edge insert pockets
• Cutting tip width of 0.0875 inches for accurate Acme profile geometry
• Cylindrical hole shape for secure mechanical clamping in compatible toolholders

Compatibility

Designed for use in on-edge threading toolholders that accept TNMA-style inserts with a 0.5-inch IC and cylindrical clamping hole. Suited for Acme threading of cast iron and steel workpieces per ISO material groups K and P.

Installation Notes

Installation should be performed by a qualified machinist or toolroom technician. Power down and lock out the machine spindle before seating or removing the insert. Ensure the insert pocket and clamping screw are clean and free of chips before securing the insert. Follow the toolholder manufacturer's torque specifications for the clamping screw and verify thread form alignment with a thread gauge before running production parts.