## 3 Results and Discussion
### Thickness Variation of Laminated Composites
The results for CoV in the laminate thickness produced on the convex corner of the mold and its variability are presented in Figure 7a,b, respectively. The grand means of the CoV and variability for convex-cornered laminates are 0.023 and -1.314, respectively. Similar to the pattern observed for concave corner results, vacuum bagging technique is the only parameter to demonstrate a statistically significant effect on the laminate thickness. SVB and DVB techniques exhibited a similar variation in thickness with CoV values 0.027 and 0.025, respectively. The high thickness variation in SVB is attributed to the corner thinning effect. MSVB technique is able to avoid a major corner thinning because the use of caul-sheet prevents a higher reaction pressure to consolidate excessively. Hence, excessive and unnecessary corner suppression is avoided. A similar finding is reported by [PERSON] et al. [26]; the CoV results reported in this study are in good agreement to theirs. Similar to concave results, curing cycles and their interaction with bagging techniques were found to be statistically insignificant. This also shows that the main factor in controlling the laminate thickness (with convex corners) is attributed to the bagging techniques and consolidation methods. The variability in the results of thickness variation in the convex corner illustrates the statistical significance of bagging techniques with an F-stat of 54.61 (>F\({}_{90\%}\)). A noticeable corner thickness variation was exhibited in SVB and DVB techniques with standard deviations of 0.061 and 0.055, respectively. The average thicknesses across the length of the laminates are plotted to better understand the variability in results, as shown in Figure 8. A major corner thinning is observed in SVB and DVB with an average of 2.058 mm and 2.076 mm, as shown in Figure 8a,c, respectively. The high CoV values achieved in SVB and DVB techniques are attributed to the noticeable corner thinning. Whereas, MSVB technique exhibited 2.082 mm thickness with a standard deviation of 0.034, as shown in Figure 8b. Figure 5: Laminates with concave corner represent (**a**) thickness coefficient of variation and (**b**) variability in the results. Despite the corner thinning, the laminates produced using SVB and DVB are 2.161% thicker than those produced using MSVB. This shows the effectiveness of the intensifier in controlling the laminate thickness by controlling the uniformity of the compaction force. An overall analysis of thickness variation showed a good consistency for the MSVB technique to not only maximize the shape conformation by avoiding bridging effect in the concave corner of the mold to prevent major corner thickening but also to prevent major corner thinning in convex corners. This study provides a basis to reduce thickness variations in laminated composites with complex shapes by an optimum selection of processing parameters for prepreg processing. For example, for a given laminate layup and geometry (corner angle), a concave molding set-up may be converted to a convex one to reduce defect levels. The results suggest that using a mold with convex corner angle is better than that of concave corner angles. Where it is necessary to use concave corners, an increase in local curvature angles and corner radii may avoid corner thickening and resin accumulation. Furthermore, the use of intensifiers could further maximize thickness uniformity. Finally, for a typical prepreg processing with various choices of bagging techniques, cure cycles and molding conditions, these results provide invaluable insight for final laminate quality. Figure 6: Thickness across the length of laminates with concave corner produced using (**a**) SVB, (**b**) MSVB, and (**c**) DVB techniques. Figure 8: \(Cont\). Figure 7: Laminates with convex corners represent (**a**) thickness coefficient of variation and (**b**) variability in the results.