On the Geometric Accuracy of RepRap Open Source Three Dimensional Printer

Abstract

In the field of additive manufacturing (AM) processes, there is a significant lack of scientific data on the performance of opensource 3D printers in relation to process parameter values. The purpose of this paper is to assess the impact of the main process parameters on the accuracy of a set of typical geometric features, as obtained with an opensource 3D printer, the RepRap PrusaMendel I2. For this purpose, a benchmarking part was set up, composed of elementary shapes, representing a series of different geometric features. By means of a DoE approach, it was possible to assess the effects of two process parameters—layer thickness (Lt) and flow rate (Fr)—on five geometric features: cube, sphere, cylinder, cone, and angled surface. A high resolution Laser Scanner was used to evaluate the variation between the acquired geometric feature and the corresponding 3D computeraided design (CAD) nominal model. On the basis of experimental results, it was possible to analyze and discuss the main effects of the abovementioned process parameters on each geometric feature. These results can help RepRap users in the correct selection of process parameters with the aim of improving the quality of prototypes.