Heli-coil A3585-02CN129 2-56 Unc Locking Insert 304 Ss

Product Description

The HELI-COIL A3585-02CN129 is a tangless screw-locking helical coil insert designed to create durable, vibration-resistant threaded connections in parent materials. Built from Grade 304 stainless steel with a bright finish, it accepts a 2-56 UNC fastener and measures 0.129 inches in overall length at a 1-1/2D length-to-diameter ratio. The locking function is produced by a deformed coil that applies radial pressure against the mating bolt thread, resisting loosening under vibration and dynamic load. Machinists, assembly technicians, and MRO professionals install these inserts to repair damaged threads or reinforce thin-wall parent material in precision assemblies.

This insert is suited for applications requiring a small-diameter, fine-pitch threaded connection with positive locking performance. The tangless design eliminates the need for tang break-off after installation, reducing debris risk inside blind holes and simplifying automated or hand installation with the appropriate installation tool. Typical applications include aerospace subassemblies, electronic enclosures, instrumentation housings, and other precision components where thread integrity and vibration resistance are critical.

Key Features

• Tangless design eliminates post-installation tang removal, reducing contamination risk in blind holes
• Grade 304 stainless steel construction provides corrosion resistance in demanding service environments
• Maximum locking torque of 20 oz-in with a minimum breakaway torque of 3.00 oz-in for reliable retention
• 5-1/4 free coils with an outside diameter range of 0.110 to 0.119 inches for consistent fit in the installed bore
• Bright finish for easy inspection and clean appearance in finished assemblies
• 2-56 UNC thread standard compatible with standard 2-56 fasteners

Compatibility

Designed as an OEM-style threaded repair and reinforcement insert for 2-56 UNC threaded holes in metal or composite parent materials requiring a screw-locking helical coil solution.

Installation Notes

Installation requires a correctly sized tang-free installation tool matched to the 2-56 UNC thread size. The parent material must be drilled and tapped with the appropriate HELI-COIL tap to achieve the correct minor diameter before insert installation. Ensure the workpiece is secured and free of chips or debris before driving the insert to the specified depth. Always follow the assembly drawing or engineering specification for insert flush depth and torque requirements on the final fastener.