Experimental investigations were carried out on the machinable wax filament using the fused deposition modelling (FDM) rapid prototyping process. The printer used for conducting the experiments was Flash Forge guider 2. The filament material used for this study was machinable wax filament of 1.75 mm diameter. Experimental trials were carried out as per Taguchi L9 orthogonal array to determine the optimum process parameter combination. The dimensional analysis of test samples were carried out in terms of change in volume of samples which is result of combine effect of deviations in all the dimensions of test sample. Four factors each at three levels was used to obtain the optimum printing parameters for better dimensional accuracy and proper printing. The four important printing parameters were taken as factor and set to analyse the significant factor affecting on printing. The complexity in printing of wax filament is taken in to consideration during the experimental study. The main effect plot for S/N ratio was plotted and ANOVA was carried out to determine the significant factor that was affecting the dimensional accuracy of the printed test samples. The results shows that there is positive deviation in the dimension along the nozzle axis and dimensionally accurate and defect free printing is achieved with layer thickness of maximum layer resolution and vertical orientation. The defects are observed in the inclined orientation samples due to support structure and delamination is detected. The Minitab software was used to analyse the results obtained from experiment. The printing parameters, which are varied for the experiment, are orientation, layer thickness, printing speed and travel speed. © 2019 SAE International. All Rights Reserved.