The rapid progress of 3D printing technology has significantly accelerated the product development process, especially prototyping. With the ability of making prototypes much faster and the possibility of processing structures using FEM analysis, the optimization of structures greatly decreases production costs and the need for overbuilding parts. In order to properly design constructions for the required purpose, it is essential to know precisely and in detail the properties of the materials used. The entire construction process is based on this. From the mechanical characterization of the materials as a base knowledge, for example from the uniaxial tensile test, material models are established and will better describe the properties even in more complex load cases. Printing samples for tensile testing on a PolyJet printer with significantly better performance than the widely available FDM types of printers questions the anisotropy phenomenon of the material, given that individual print layers are significantly smaller, more precise and polymerized by photopolymerization. For this reason samples were printed in two directions, longitudinal and transverse, in comparison to the axis of tensile testing and are tested at different test speeds. By reading the data, the potential dependence of the mechanical properties on the testing and production conditions are observed, and then they are characterized using a program code that performs fitting, the adaptation of the experimental data to the material models. Such an adjustment will provide values of material constants that can further be used to calculate loads in other load cases.