## 3 Three-Dimensional Printing of the Mould  
In this study, the direct 3D-printed TDV moulding method was used with the Ultimaker S5 printer (Ultimaker, Utrecht, The Netherlands). Although this 3D-printed mould does not offer the strength and durability of conventional moulding tools, it has the advantage of being very cheap, fast in manufacturing, and very useful for small series and prototypes. Using this method with a 3D-printed mould allows the production of parts with very high mechanical performance without the need for additional specialised equipment or tools. Although other types of filaments can also be used, polylactic acid (PLA) has been found to offer high precision, low shrinkage, and ease of printing, making it an excellent choice for mould making [51; 52; 53]. The affordable cost of PLA is still a determining factor in choosing it for mould making. Compared to filaments made from acrylonitrile butadiene styrene (ABS) or nylon, the filament made from PLA is about 20% cheaper than these. This makes it a suitable choice for moulds that require a large amount of material but for projects that do not have a large budget. The environmentally friendly and sustainable aspect of PLA is due \begin{table}
\begin{tabular}{c c} \hline \hline
**Process Parameters** & **Value** \\ \hline Volume filled [dm\({}^{3}\)] & 3.38 \\ Cavity design & Open \\ Clamping force [Nm] & 20 \\ Mould tolerance [mm] & \(\pm\)0.2 \\ Ejector system & Rod type \\ Moulding temperature [\({}^{\circ}\)C] & 20 \\ Moulding pressure [bar] & 20 \\ Fibre to resin ratio [\%] & 60–40 \\ Compression time [h] & 48 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Mould design parameters. Figure 3: Mould assembly drawing. to the fact that it is made from renewable raw materials such as corn or other plants, making it an environmentally friendly material. PLA production generates lower CO\({}_{2}\) emissions and uses less energy than petroleum-based materials such as ABS. PLA is also biodegradable, which means that it can be broken down naturally by microorganisms in the environment [54]. This characteristic makes PLA a suitable choice for applications that require minimal environmental impact [55]. In order to manage the 3D printing of a mould that exceeds the printing dimensions of the 3D printer in the X and Y directions, an alternative solution was needed to divide the mould into smaller sections that can be printed separately. However, a major drawback associated with this method is that once the initial mould geometry is split, the accuracy of the mould decreases along the direction in which it is split. To compensate for this problem and to ensure a correct and accurate assembly of the resulting mould from individual sections (Figure 4a), a puzzle-type assembly (Figure 4b) was chosen. Due to the geometry of the cylindrical section and similar dimensions there is a risk of mixing up sections within the same mould. To combat this risk, each part is marked as shown in Figure 4b. This also ensures the correct assembly of the moulds and the alignment of the fixing and assembly bores. By using this assembly method, each section of the mould can be accurately and securely positioned and clamped, ensuring the correct geometry and stability of the final mould. It is essential that the assembly process is well planned and that each part fits perfectly into the puzzle template, avoiding discrepancies or clearances that could affect the final mould. This approach offers a practical and efficient solution for 3D printing large-sized moulds using a 3D printer with limited capacity. Precise mould splitting and assembly allows large moulds to be manufactured affordably and efficiently without compromising the quality and accuracy of the final mould.