The insert consists of a single piece of wire, set into a helical shape. The thread of a coiled insert is multi-directional, which means the diamond shape of the wire is angled to create corresponding internal and external threads. This allows the walls of the insert to be very thin.
Coiled threaded insert tang
The tang is the last part of the wire and it is bent inwards to create a bar across the bottom of the insert. It acts as a guide for insertion and is usually snapped off after installation, which is why there is also a small notch on the last thread. There are now tangless coiled inserts available, which are beneficial if a loose tang could cause damage to any mechanics.
Coiled threaded insert kits
Coiled inserts can be purchased in kits which include all the tools needed for installation. Coiled threaded inserts require a special-sized tap because the inserts are not self-tapping.
