## 4 Results  
The raw material savings for the individual constructions are shown in the graphs (Figures 7-10) taking into account both variants of reduction of machining allowances. This mainly concerns savings in wood and MDF obtained by reducing the width of the frames in variant 1, and savings in wood-based panels obtained by reducing the height and width of the input panels in variant 2. The savings are presented both in absolute terms and as a percentage of the amount of material used in the existing technology. Figure 8: Material savings obtained by reducing the machining allowance in construction 2. Figure 7: Material savings obtained by reducing the machining allowance in construction 1. Due to the fact that construction 1 is based on wide, wooden frames, it was possible to achieve a large reduction in machining allowance by as much as 4 mm. Therefore, the saving of wood in variant 1 amounted to over 0.5 m\({}^{3}\)/1000 pieces. The larger the leaf dimensions, the slightly greater the saving. In percentage terms, this results in a 2.2% reduction in frame volume. In variant 2, when reducing the machining allowance by decreasing the input dimensions, savings of approximately 0.250, 0.125, and 0.06 m\({}^{3}\)/1000 pieces were obtained for particleboard, plywood, and HDF filling materials, respectively. This saving is also slightly related to the leaf dimensions. Its absolute value increases for increasingly larger leaves, while in percentage terms, as the allowance is not related to leaf dimensions, it decreases from about 0.80% for the smallest leaves to about 0.68% for the largest ones. In construction 2, invariant 1 of determining the machining allowance, the allowance was assumed to be reduced by only 2 mm due to the smaller width of the frames than in construction 1. This naturally resulted in reduced lumber savings. This gives a saving for all but the widest leaves of just under 0.2 m\({}^{3}\)/1000 pieces, which is about 2% of the material in the construction. In variant 2, the savings were mainly in particleboard, due to the much wider element width than plywood. For all leaf widths the savings were over 0.15 m\({}^{3}\)/1000 pieces. The saving on plywood was negligible, due to the small width of the elements in the leaf. In lightweight construction 3, it was only possible to reduce the machining allowance in variant 1 by 2 mm (from 8 mm to 6 mm). The filling here was made of paper honeycomb. Reductions were made in the width of frames made of pine and MDF, with the saving in MDF being much greater, due to the larger amount of this material in the construction, and amounting to 0.15 m\({}^{3}\)/1000 pieces. On the other hand, due to the small cross-sectional dimensions of the frames, the savings expressed in percentage terms of both materials were high and amounted to almost 3%. Construction 4 was distinguished by the use of oak wood, which is more valuable than pine. Only the lower internal frame was made of pinewood. This creates the potential for savings of this wood in variant 1 with a reduction in machining allowance from 12 mm to 8 mm. This results in a significant saving of approximately 0.4 m\({}^{3}\)/1000 pieces. In percentage terms, this is also an extremely advantageous situation, as it allows us to save  
Figure 9: Material savings obtained by reducing the machining allowance in construction 3.  
over 4% of the material in each construction variation. The saving of pinewood is negligible due to its less important role in construction 4 of the door leaf. In variant 2, particleboard savings were also significant, ranging from over 0.35 to over 0.4 m\({}^{3}\)/1000 pieces, depending on the nominal width of the leaf. In terms of quantitative analysis of wood material savings, general observations can be made. The material savings expressed in physical units depend to some extent on the overall dimensions of the leaves. The larger they are, the more material can be saved in both variants of determining the machining allowance.