Self-Tapping Screws

Self-Tapping Screws

Self-tapping screws are often used to fasten plastic parts together. Self-tapping screws are available both in thread-cutting type as well as thread-forming type.

 

Thread Forming
Pros	Cons
High tensile values	High hoop stress, boss has to be designed to withstand this stress
High amount of torque to strip threads
Large number of cycles of assembly and disassembly possible	Stress relaxation possible
Suitable for plastics that are non-brittle	Not suitable for brittle plastics

 

Thread Cutting
Pros	Cons
Lower Hoop Stress	Lower Tensile Pullout
Suitable for brittle plastics	Lower amount of torque to pull the threads

 

Links: Article link.