## 4 Discussion  
In this work, we developed a method that can be implemented in almost any R&D lab for fabricating custom moulded-pulp geometries. The material used, a blend of cardboard and white glue, was engineered to exhibit mechanical properties similar to those of industrial MP structures. This method allows for the classification of geometries based on their ability to absorb shocks. The setup is straightforward, requiring only a standard 3D printer, an oven, and a crash test bench. It enables the evaluation of multiple geometries within a two-day period. First, we manually fabricated and dried moulded-pulp plates from the cardboard/glue mixture. Static tests were conducted on these samples to identify the optimal proportion of white glue required to match the Young's modulus of industrial MP structures. In the next phase, we used PLA 3D printing to create moulds of various shapes, and devised an efficient method for correctly positioning the material within the moulds and drying it in an oven. These steps led to successful crash tests, the results of which were validated throughout FEM simulations. Namely, cones and pyramids pins were tested. Such geometries were also tested years ago in [21], leading to the conclusion that both structures have very close mechanical dynamic behaviour. However, this study used expanded polystyrene foams instead of paper. In our study, we could show that conical shapes have a better dynamic strength than pyramidal ones, results that are consistent with the ones from [22], where similar geometries were crash tested. Finally, the study carried out in [7] demonstrates that structural factors such as the sample geometry have a higher influence on the shock absorption capabilities than the material properties such as density or thickness. This result confirms the importance of optimizing the shape of the MP packages, which is what our method tends towards. The approach presented in this study effectively demonstrates the feasibility of fabricating and roughly characterizing tailored moulded-pulp pin geometries with relative ease. By using this method, significant advancements can be made in accelerating the prototyping capabilities for optimizing MP pins in industrial applications. However, despite the promising results, several challenges and limitations remain that need to be addressed for this approach to become more broadly applicable and efficient. * Fabrication challenges with complex geometries: Certain geometries are inherently difficult to fabricate using this method, particularly those involving vertical walls. The vertical edges present a significant challenge because they complicate the unmoulding process, leading to potential damage or deformation of the structure upon removal from the mould. For example, a cylindrical geometry was manually fabricated as part of this study, but the process was not entirely successful. The manual approach introduced inconsistencies and defects, highlighting the limitations of the current fabrication method when applied to more complex or vertically oriented designs. * Time-consuming fabrication process: The entire fabrication process currently spans two days: the first day is dedicated to pin design and 3D printing, while the second day is required for material preparation and the subsequent drying phase. This timeline is not optimal for industrial applications where rapid prototyping is essential. The drying phase, in particular, is time-consuming due to the necessity of slowly heating the pulp to remove excess water. * Surface quality and structural integrity: The presence of excess water in the pulp mixture during the moulding process poses another limitation. Because the water content prevents the mould from being fully closed during drying, the resultant structure tends to have a smooth surface only on one side. This asymmetry can lead to inhomogeneities within the material, creating localized weaknesses that could compromise the structural integrity of the final product.