Manufacturing methods such as vacuum infusion will typically yield a higher fiber volume fraction than hand laminate methods. Therefore with equal amount of fibers a vacuum infused laminate is thinner than a laminate produced by hand lamination. In the case of a sandwich panel with relatively thin skins in relation to the core thickness, the global panel strength and stiffness will remain more or less unchanged. However resistances to local loads such as impact are likely to differ and such differences may need to be taken into account in the engineering process. Two sandwich panel lay-ups were designed and manufactured in accordance with the preliminary ISO standard, (Hull construction - Scantlings - Part 5: Design pressures for monuhulls, design stresses, scantling determination); one infused and one hand laminated. The panel lay-ups were chosen to represent a 'typical' bottom panel of a 38 ft. power boat. The outer skin thickness of the vacuum infused panel were 36% thinner and 27% lighter than the hand laminated panel. Impact testing on the outer skin of each panel showed that the resistance against a local impact was more or less the same.
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