Heli-coil A3585-02CNW129 2-56 Unc Locking Insert

Product Description

The HELI-COIL A3585-02CNW129 is a tangless screw-locking threaded insert designed to create a durable, vibration-resistant female thread in a tapped hole. Manufactured from Grade 304 stainless steel with a dry film lubricant finish, this insert measures 0.129 inches overall length and is sized for 2-56 UNC thread applications. The locking feature is achieved through a deformed coil section that grips the mating fastener, resisting loosening under dynamic loads. Installation does not require a tang break-off step, which reduces debris risk and simplifies the process in blind-hole applications. This insert is used by assembly technicians, aerospace fabricators, and precision equipment maintenance professionals.

This insert is suited for applications where a 2-56 UNC thread must be installed or restored in soft or damaged base materials including aluminum, magnesium, and plastic substrates. The 1-1/2D length-to-diameter ratio provides a solid thread engagement zone appropriate for fastener loads common in light mechanical and electronic assemblies. The tangless design makes it well-suited for cleanroom and close-tolerance environments where tang fragments cannot be tolerated.

Key Features

• Tangless design eliminates tang removal and reduces debris in blind-hole installations
• Grade 304 stainless steel construction resists corrosion in harsh or washdown environments
• Dry film lubricant finish reduces installation torque and galling during drive-in
• Maximum locking torque of 20 oz-in with a minimum breakaway torque of 3.00 oz-in for reliable fastener retention
• 5-1/4 free coils with outside diameter range of 0.110 to 0.119 inches for consistent hole fit
• 1-1/2D length-to-diameter ratio provides full thread engagement in thin-wall and shallow-boss applications

Compatibility

Designed as a replacement or new-installation locking insert for 2-56 UNC tapped holes in applications requiring a stainless steel, tangless, dry-film-lubricated insert with a 1-1/2D engagement length.

Installation Notes

Installation requires a correctly sized 2-56 UNC STI (Screw Thread Insert) tap to prepare the host hole to the proper oversize diameter before insert drive-in. Use the appropriate HELI-COIL tangless installation tool to drive and seat the insert without damaging the coil. Verify hole depth and thread engagement length before installation. Always follow the equipment manufacturer's torque specifications for the mating fastener after insert installation.