Enhancing properties in material extrusion process by developing alternating layer printing method using RepRap code

This study investigates the utilization of various G-code options and the combination of different code types as a primary strategy to enhance the mechanical properties of the build structure. The focus lies on printing alternating layers with varying thicknesses to improve the strength of material extrusion (MEX) components. The objective is to reduce the inter-layer porosity between layers and determine the necessary overlap percentage to decrease the intra-layer porosity. Through systematic analysis of combining G codes of 0.1 mm and 0.2 mm layer heights (LH), found single alternating layer resulting in significant enhancements in mechanical strength, approximately 15.31% compared to 0.1 mm layer height and 10.62% compared to 0.2 mm layer height in RepRap programs. However, as the count of alternating layers increases, part mechanical strength approaches that of standard printed samples. The level of intra-layer porosity depends on the determined overlap percentage, indicating the advancement of the nozzle path over neighbouring printed beads. To accommodate diverse layer heights, overlap percentages have been calculated, accompanied by suggested formulas. Alternating layer printing method improve mechanical properties without affecting dimensional accuracy of alternating layer samples compared to conventional layer printing processes. This approach also resulted in a reduction in printing time by 15.09% compared to conventional constant layer height printing methods.