These fasteners have been designed to assemble unconventional materials, such as ultra high-strength steel and bioplastics.

You can buy threaded inserts (see video below ... Then he used a hot air gun to only heat the metal (so as to reduce the chance of deforming the actual part). Once it was hot (about 15 seconds ...

Heat-set inserts are stock parts that add threads to a part made from a thermoplastic ... we risk getting the iron tip stuck in the insert. Remember: metal expands when it heats up and contracts ...