/// FOLDING A SANDWICH BOAT
IMAGINED BY: Herbert Funke, Marcel Bilow
KEYWORDS: layered construction, load-bearing, low-cost, structure, composites
A glass-fiber-reinforced plastic (GRP) boat was developed during a plastic seminar.
The sandwich core, providing structural height, serves as a lost mold: thus, no additional molding forms are needed. The boat is constructed in 4 stages: first, the foam core is laid out and coated with GRP on one side. Pressure is then applied by a deflated, enveloping, airtight plastic bag. When the coating is cured, this plane element is turned around, and the foam core is cut along the folding pattern. Tests showed that the outer GRP skin does not delaminate during the folding. Finally, the inner side is also coated with GRP, keeping the folded form in shape and providing the final stiffness.
This project was supported by the following companies: Gebr. Becker GmbH & Co KG / Wuppertal (vacuum pump), Hyco-Vakuumtechnik GmbH / Krailling, R&G GmbH Faserverbundstoffe / Waldenbuch (GRP ), epurex films / Walsrode (foil for vacuum pressure)