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Current demands on quality are the engine of searching for new progressive materials which should ensure enough durability in real conditions. Due to their mechanical properties, however, they cannot be applied to conventional machining methods. In respect to productivity, one of the methods is the finding of such machining technologies which allow achieving an acceptable lifetime of cutting tools with an acceptable quality of a machined surface. One of the mentioned technologies is trochoidal milling. Based on our previous research, where the effect of changing cutting conditions (cutting speed, feed per tooth, depth of cut) on tool lifetime was analysed, next, we continued with research on the influences of trochoid parameters on total machining force (step and engagement angle) as parameters adjustable in the CAM (computer-aided machining) system. The main contribution of this research was to create a mathematical-statistical model for the prediction of cutting force. This model allows setting up the trochoid parameters to optimize force load and potentially extend the lifetime of the cutting tool.

In the present time there are many different plastic materials and composite materials suitable for 3D printing by deposition of semi-melted material. The proper selection of correct material with suitable material properties is dependent on the situation how the produced 3D model should be used. If we need to take into account just the visual look of used material or also the mechanical properties as strength is important for loaded models for final use. The aim of this paper is to publish outputs of experimental testing for 3D models from selected materials with regards to mechanical properties of produced testing parts. Produced 3D models are from PLA biodegradable thermoplastic. Models are prepared on Fused Deposition Modelling (FDM) 3D printer. Testing is based on prepared full factors experiment with four factors on its two levels. Measured values are Tensile strength of PLA testing 3D models. In the same time there are gathered information regarding the 3D printing process and compared to measured tensile strength values for each sent of testing parts. All the measured data are statistically evaluated also by Analysis of Variance (ANOVA method).

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This contribution deals with the accuracy of machining during free-form surface milling using various technologies. The contribution analyzes the accuracy and surface roughness of machined experimental samples using 3-axis, 3 + 2-axis, and 5-axis milling. Experimentation is focusing on the tool axis inclination angle—it is the position of the tool axis relative to the workpiece. When comparing machining accuracy during 3-axis, 3 + 2-axis, and 5-axis milling the highest accuracy (deviation ranging from 0 to 17 μm) was achieved with 5-axis simultaneous milling (inclination angles βf = 10 to 15°, βn = 10 to 15°). This contribution is also enriched by comparing a CAD (Computer Aided Design) model with the prediction of milled surface errors in the CAM (Computer Aided Manufacturing) system. This allows us to determine the size of the deviations of the calculated surfaces before the machining process. This prediction is analyzed with real measured deviations on a shaped surface—using optical three-dimensional microscope Alicona Infinite Focus G5.