Assortments include various sizes of tapered inserts, a soldering iron, a ceramic insulation tube, and installation tips. The tapered shape makes it easy to guide these inserts into a hole during installation. Use a drill bit to create a straight hole, then taper the top half. Heat inserts with the soldering iron so that they melt the plastic when installed. As the plastic cools, it solidifies around the knurls and ridges on the insert for excellent resistance to both torque and pull-out. Made from brass, they’re corrosion resistant, electrically conductive, and nonmagnetic.

Install these inserts into plastic parts to create a secure base for fasteners. Also known as Chevron and headed inserts, they are often used to strengthen mounting holes on brittle plastics, such as on 3D printed parts. Unlike plastic threads, which wear down with repeated use, these threads hold their shape over a long life. Press inserts into straight holes that have been drilled, printed, or molded into plastic parts, then heat them with a soldering tip to melt the surrounding plastic. As the plastic cools, it fuses to the sharp, diagonal ridges around the inserts, which withstand torque and prevent the inserts from being pulled out. The interior is fully threaded, so you can access the threads from both sides of a through-hole.

Flanged inserts have a wider end than standard inserts, which gives them a larger load-bearing surface and makes them harder to pull out. The flange also gives you a larger contact area for soldering. When threading into the flanged side, these inserts prevent over-tightening, which can cause brittle plastic to crack.

Made with lead, brass inserts are stronger than aluminum and other brass alloys but not as strong as 18-8 stainless steel inserts. They have good corrosion resistance.

Aluminum inserts are one-third the weight of brass and stainless steel inserts, have good corrosion resistance in wet environments, and are lead-free. Since they’re lead-free, they can be safely recycled.

18-8 stainless steel inserts are stronger than brass and aluminum inserts, have excellent corrosion resistance, and are lead-free. Since they’re lead-free, they can be safely recycled.