Application of Optical Measurements to Assess Form Deviations of Cylindrical Parts Made Using FDM Additive Technology.

Fused Deposition Modeling (FDM), also known as Fused Filament Fabrication (FFF), is a widely used additive manufacturing (AM) method for thermoplastic materials due to its low cost, accessibility, and ability to produce fully functional machine parts. Cylindrical components, common in mechanical devices, require precise dimensional and form accuracy to ensure long service life. To assess their quality, cylindricity deviation measurements are essential, as they reveal defects generated during the printing process. This study investigates the potential of optical scanning for measuring form deviations specifically cylindricity and roundness of ABS components manufactured via FDM. The influence of printing orientation (0°, 45°, 90°) on dimensional accuracy was examined using experimental models comprising three series of ten samples each, with identical process parameters except orientation. Measurements were performed using a Zeiss Prismo Navigator (Zeiss, Oberkochen, Germany) coordinate measuring machine and an ATOS II Triple Scan (GOM, Brunswick, Germany) optical scanner. Results indicate that print orientation significantly affects cylindricity deviation. The lowest deviations were achieved for specific orientations, offering guidelines for producing cylindrical surfaces of acceptable quality. The findings also show that optical scanners are not suitable for precise form deviation analysis in FDM-printed parts, confirming the higher accuracy of tactile coordinate measurement methods.