In this research, we developed an analytical model by deriving a mathematical formula to simulate extrusion behaviour with varying printing parameters, such as printing temperature, filament dimensions and printing speed. To validate the analytical model, filament morphology across 3D-printed objects with scaled sample sizes is initially characterized using a micro-CT scanner. Subsequently, uniaxial compression tests are conducted on the parts to assess their mechanical properties. The resulting strain-stress curves act as indicators, revealing whether the properties of the layer-by-layer interface are consistent across the 3D-printed samples. Consequently, consistent filament dimensions and comparable curves demonstrate the controllability of mesostructure through the application of extrusion modelling. With the validated extrusion modelling, additional possibilities emerge for predicting the properties of 3D-printed polymers once the printing parameters are known. This predictive capability will significantly contribute to a comprehensive understanding of the intricate interplay between printing parameters and sample size, revealing their combined influence on the properties of 3D-printed materials.