Heat-Set Threaded Inserts are a great option for 3D printed parts or making repairs to any thermoplastic part. They provide a much stronger connection than simply threading screws into the plastic. Brass inserts will also last much longer than plastic threads and are less likely to cross thread which makes them ideal for parts that are assembled and disassembled often. These inserts can be easily and quickly installed by heating them with a standard soldering iron on a low-heat setting and using the soldering iron's tip to press the insert into place.  The melted plastic will flow around the knurls and ridges on the insert as it is pressed in and solidify when cool, locking it in place.

For optimum strength the manufacturer recommends that the tapered inserts should be used in holes designed with an 8° total taper to the sides. We find that due to the irregular surface finish from 3D printed layers that these inserts are very forgiving and will usually work well in holes designed with straight sides as well. These 1/4" inserts are tapped for SAE 1/4"-20 threads.

Specifications:

• Maximum Insert Diameter: 0.375" (~9.52mm)
• Tapered End Diameter: 0.354"(~8.99mm)
• Optimum Installation Hole Size:   ~0.349" (~8.86mm) with 8° outward taper.
• Length: ~0.3" (~7.62mm)
• Vanes: 1
• Material: Brass

Design tips for using Heat-Set threaded inserts

Ideally tapered inserts are meant to be placed into holes designed with an 8° inward taper. However when using the inserts on 3d printed parts, we find that the gaps between the stacked layers, and the tendency of FDM style 3d printers to produce slightly undersized holes usually compensates for this. However you may have to experiment with your set-up if you need the strongest connection possible for your application.