Thread-forming screws are comparable to thread-reducing screws in they get rid of materials to create threads. But as opposed to eliminating material, they displace it, relocating it away from just how. This type of thread types a very limited grip and it is often located in various softwoods or plastics. https://andywdfhi.wssblogs.com/29396584/detailed-notes-on-types-of-screw-heads-with-pictures