Dimensional and Shape Accuracy of Foundry Patterns Fabricated Through Photo-Curing

This paper deals with the potential use of the PolyJet Matrix (PJM) technology and digital materials to fabricate foundry patterns. The primary purpose of the study was to assess the dimensional and shape accuracy of additively manufactured objects by determining the draft angle as well as the roundness, waviness and roughness parameters. The experiments were conducted for cylindrical samples printed using VeroWhite liquid polymer resin. The analysis focused on the relationship between the build direction and the geometry and surface finish of prints. Three different orientations, i.e. 0 degrees, 45 degrees and 90 degrees, were considered. The surface texture analysis involved comparing the statistical, graphical and numerical data, including calculation results obtained with the wavelet transform method. The findings confirm that the build direction has a significant effect on the dimensional and shape accuracy of prints and that the PJM technology can be used to fabricate precise foundry patterns, especially in investment (lost-wax) casting.