Shrinkage Analysis of a Constrained Thin Walled Injection Molded Component Using a Traditional Flatbed Scanner and Photometric Techniques

A study was performed to determine the effects of varying the wall thickness and material glass fiber concentration for parallel and perpendicular shrinkage rates for a constrained thin-walled box shaped component.

An analysis of the shrinkage for the bottom portion of a 3 dimensional constrained thin walled injection molded component was performed using measurements made from bitmap images of the components that were obtained from a traditional flatbed scanner. The shrinkage rates were determined by comparing mold cavity hatch lines to the correlating transposed hatch lines on the plastic molded component. The perpendicular and parallel shrinkage rates were determined and are discussed as a function of thickness and glass fiber content. A wide range of processing control factors was used in the study.