3D Printing and Product Design For Plastic Snap-Fits and Hinges

Abstract

The aim of this thesis project is to design and 3D print plastic snap-fit and hinges boxes which are used in daily life. All the design was done by using SolidWorks 2021 and 3D printing was successfully done by using the Creality Ender-3 printer and PLA plastics. SolidWorks FEA simulation was used to analyze the stress of the snap-fits and hinges. The stress results found from the simulation were quite accurate compared to theoretical calculations of the cantilever snap-fit box with hinges as the error was only 11%. Whereas cantilever snap-fit and annular snap-fit have errors of 56% and 83% respectively. The maximum stress of the cantilever snap-fit box and cantilever snap-fit box with hinges in simulation results are 127.964 MPa and 90.91 MPa. And the theoretical result is 81.75 MPa. Moreover, the results of the annular snap-fit in simulation and theoretical stress analysis are 0.775 MPa, and 0.422 MPa respectively. Therefore, in the printing parts, there was some uneven area in the cantilever snap-fit box hinges as support used while printing. Otherwise, the printing process of the cantilever snap-fit box and the annular snap-fit box was successful. There are a few types of snap-fit which are cantilever, annular and torsional. In this thesis project, cantilever and annular snap-fit were presented. On the other hand, hinges analysis has also been presented. Though there have quite a lot of errors in theoretical calculations one can easily acknowledge from this research about different types of snap-fits and hinges, 3D printing, and analytical ways of calculating the stress and mass of any material.