Plastic material selection is a very important decision for your custom molding project. It is wise to consider the part’s intended application and functionality as you begin the process. Things like strength, performance, durability, flexibility, color and texture all need to be considered. The goal is to make sure you achieve a functional and aesthetically pleasing (surface finish) part without defects such as sink marks, warpage and out of spec dimensions and tolerances.
Material shrinkage and melt flow rate also need to be considered. If the material needs to be changed after the mold is produced, and the shrink rate is different for the new material selected, then the part’s dimensions will not be to the original spec. This may or may not cause problems with assembly and function.