## 3 Materials and Methods
The model utilized for adhesion testing was specifically designed to evaluate adhesive properties across various substrate materials. * Characteristics of the PETG model: the PETG model was designed with a specific geometric form that allowed for easy fixation within the jaws of the measuring instrument. Figure 2: The Emsyst EMS20-5 KN sensor with the converter EMS650. Its form was selected to evaluate adhesion properties under controlled conditions, ensuring consistent and replicable testing scenarios. * Geometric design for adhesion testing: the PETG model's design encompassed specific features intended to evaluate adhesion properties under various conditions, enabling controlled and systematic investigation of the bonding force between the model and diverse print bed materials. As depicted in Figure 3[16], two materials were considered for the execution of the test model, which could be deemed the most commonly used or widely recognized. However, the material PLA was excluded from this process, characterized as the \"most straightforward\" in terms of its utilization within FFF technology and the printing process itself. As highlighted in Table 2, discrepancies in bed temperatures, melting temperatures, and other properties essentially disqualified PLA from this process. PLA is a material widely acknowledged for often not requiring the heating of the print bed in many instances. With appropriate initialization layer settings, its adhesive properties are deemed sufficient for nearly any commonly used uncontaminated surface. Based on the preceding selection of materials and components for the measuring apparatus, its utility, and integration within FFF setups allow for the following observations: \begin{table}
\begin{tabular}{l c} \hline \hline Printing temperature & 255 \({}^{\circ}\)C \\ \hline Print bed temperature & N/A \\ \hline Printing material & PETG; 1.75 mm \\ \hline Nozzle diameter & 0.40 mm \\ \hline Layer cooling & Off-for all layers \\ \hline Print speed & 50 mm/s \\ \hline Number of outline perimeters & 3 \\ \hline Number of top and bottom layers & 2 \\ \hline Infill & 100\% \\ \hline Infill pattern & Grid \\ \hline Layer height & 0.23 mm \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Description of the chosen parameters for the production of samples. Figure 3: Graphical representation of generally known properties of PLA and PETG materials. * The device's frame will be compact and adaptable to build plates of various types of equipment. * The construction of the frame must possess adequate stability and rigidity while enabling the placement of all necessary components of the measuring system. * The motion or detachment of the model from the print bed must be uniform and monitored throughout the entire process. The apparatus must include a drive mechanism and means for transforming its movement. * The model for testing adhesive properties must be compatible with the designed apparatus. * The same sample and the same FFF equipment must be used for each experimental measurement. * The test model must be consistently positioned at the center of the print bed to ensure the correct alignment of the measuring device and the model. * Measurements are conducted by the same individual under stable laboratory conditions. * Models used for optimizing the printing process for a new type of print bed are not included in the measurements. Several designs of the measuring device were created based on these requirements. The following chapter introduces one of the suitable prototypes, thoroughly describing its operational principles, and highlighting the obtained results and issues.