Vargus 51866 Threading Insert 8 Tpi Acme 3G Solid Carbide

Product Description

The VARGUS 51866 is a solid carbide laydown threading insert designed for right-hand external Acme 3G thread cutting at 8 threads per inch (TPI). It features a TiN coating applied via PVD process, which extends edge life across a broad range of workpiece materials. The insert carries a 3ER style designation with a 9.53 mm inscribed circle (3/8 inch) and a thickness of 3.60 mm. The 29-degree included angle is correct for Acme thread form geometry. Machining professionals and CNC lathe operators use this insert for precise, repeatable Acme thread profiles on external features.

This insert is suited for threading operations on a wide range of metallic workpiece materials, including steel, stainless steel, cast iron, non-ferrous alloys, high-temperature alloys, and hardened materials, reflected in its universal primary workpiece material rating covering material codes H, K, M, N, P, and S. It fits standard 3ER insert pocket toolholders and is commonly used in production and job-shop CNC turning environments where Acme thread forms are required on lead screws, actuators, and power transmission components.

Key Features

• Solid carbide substrate with PVD-applied TiN coating for extended tool life
• 8 TPI Acme 3G external thread form with 29-degree included angle
• 3ER insert style with 9.53 mm (3/8 inch) inscribed circle
• Right-hand cutting orientation for standard external threading passes
• Universal material compatibility across steel, stainless, cast iron, non-ferrous, and high-temp alloys
• Conforms to ANSI B1.5:1988 Acme thread standard; manufactured under ISO 9001:2008 quality system

Compatibility

Designed as a direct-fit replacement for standard 3ER insert pocket toolholders used in external Acme 3G threading applications. Verify toolholder pocket geometry and insert seating against the 3ER style specification before installation.

Installation Notes

Installation should be performed by a qualified machinist or CNC tooling technician. Power down and lock out the machine spindle before seating or replacing the insert. Use the appropriate torque wrench and insert screw to secure the insert in the pocket - do not overtighten by hand. Confirm insert seating and thread-form alignment with a test pass before running production cuts.