Integrated Study of Surface Roughness Parameters and Dimensional Accuracy in FDM 3D-Printed

Abstract

This study focuses on analysing how surface quality and dimensional accuracy are affected by the measurement processes and printing parameters of a 3D-printed timing belt pulley of a Dacia Logan engine. This project is aiming to investigate how different 3D printing parameters and PLA filament brands influence surface quality while also testing the consistency of prints made with identical settings. The parts were produced using the FDM method on a Bambu Lab A1 Combo printer, known for its high speed, precision, and automatic calibration features. Surface roughness, affected by factors such as layer height, print bed temperature, and cooling rate, was measured using a high-precision Jenoptik Waveline W912RC profilometer. The results showed that smaller nozzle sizes and finer layer heights achieved smoother surfaces, with varying nozzle dimensions of 0.2mm, 0.4mm and 0.6mm. Perpendicular measurements showed consistent values, confirming surface profile stability. The study concluded that both printing parameters and filament brand have a measurable impact on surface roughness and that even under identical conditions, environmental factors may cause minor variations. Continuous parameter adjustment and monitoring were identified as essential for optimising surface quality, reducing defects, and meeting ISO standards for surface roughness and measurement accuracy.