Self-tapping screws are screws that can form their own threads as they are driven into the material. Plastic requires a specially designed thread profile as tapping screws used with steel can result in residual stresses in the plastic that can degrade the structural integrity of the assembly. Plastic screws give you more flexibility and quickly assemble components with fewer fasteners.
When looking into self-tapping screws, the first step is to decide what type of self-tapping screws are best suited for the application. Self-tapping screws for plastic application are classified into two categories: thread-forming and thread-cutting. To help chose the right screw category, it’s important to understand the type of plastic you are fastening into: thermoplastic or thermoset. Below is a brief description of each category.
Thread-forming screws, generally, function best in thermoplastic materials. Thread-forming screws produce no waste as the plastic that is displaced to create the thread flows back into the root of the thread resulting in a very secure fit.
ecosyn®-plast is a great option for a thread-forming screw for plastic. These screws are designed to easily penetrate the material without causing stress to the material. Check out some advantages of ecosyn®-plast:
- Low driving torque and high stripping torque
- High breaking torque and tensile strength of the screw
- Excellent security against vibration
- Low risk for cracking the base material
- No setting of the assembly due to excessive relaxation of the plastic material
Thread-cutting screws are designed for thermoset material. These screws remove material because they have cutting edges. Thread-cutting screws have a smaller flank angle to reduce installation torque while increasing surface area which results in a higher pullout force.
If you have questions about self-tapping screws for plastic or need help in deciding on a fastener, contact us at ProvenProductivity@bossard.com. Our experts can help you get the materials you need for a successful project. We are also prepared to provide you with technical advice and we can even provide field-related assembly tests for you in our laboratory to help with application technique.
Self-Tapping Screws for Plastic by Bossard