Modeling of FDM 3D printing for improved performance

Fused Deposition Modeling (FDM)-type 3D printing is exploding in popularity and is the fastest growing type of rapid prototyping (RP) technology. The quality and mechanical properties of a FDM print are largely dependent on various print parameters. This study aims at optimizing two important print parameters, nozzle diameter and layer thickness, to obtain the best print patterns for a multi-head FDM 3D printer. Four test blocks with different shapes and volumes were used for calibration and comparison of computer models of several print patterns. Three print patterns (Single Layer, Bi-Layer and Interspersed Layer) were developed and computer models were created for each. The volume fraction, print times and surface smoothness for each block, using each model, were determined. It was determined that block size and size of the bead have no effect on the volume fraction of any single nozzle FDM 3D printed part. Results obtained from a Bi-Layer Pattern Model showed a reduction in print time by over 40% compared to a Single Layer Pattern, but volume fraction stayed the same. The Interspersed Layer Pattern has the highest inherent volume fraction and can be used to 3D print high quality composite structures. The increased volume fraction for the Interspersed Layer Pattern means that strength and stiffness is improved over the Single Layer and Bi-Layer Patterns respectively. The optimum Interspersed Layer should have a DS/DL approximately equal to 0.42 and tL/tS = 3 for a two nozzle system. A Leapfrog “Creatr” 3D printer was modified to have four nozzle heads, but delays prevented verification of the print patterns on the Leapfrog and printing composite filament on the modified Leapfrog