Cabin cruiser: Making the most of a mirror finish
The hull mirror-like gel coat finish on the Daedulus 30 cabin cruiser was achieved through a combination of Marine Concepts’ (Lee-on-the-Solent, Hampshire, U.K.) mold design experience and fabrication techniques and materials provided by Scott Bader (Wollaston, Northamptonshire, U.K.).
A new fiberglass-reinforced polymer cabin cruiser, Daedalus 30, made its debut at the PSP Southampton Boat Show (Southampton, U.K.) in September 2010. Although it is only 9.3m long by 3.2m wide (30.75 ft by 10.5 ft), it caught the attention of many seasoned composites experts at the show, thanks to its high-gloss gel coat surface finish and the overall build quality. Its exceptional surface was achieved by Marine Concepts Ltd. (Lee-on-the-Solent, Hampshire, U.K.) using marine composite products from Scott Bader Company Ltd. (Wollaston, Northamptonshire, U.K.).
Daedalus 30 is Marine Concepts’ first-ever luxury cabin cruiser. The yacht is the result of a four-year collaboration with U.K.-based designer John Moxham, who conceived the vessel with a sharp V-section forward, a large radius amidships, down-angled spray rails and a big radius at the stern. Its dynamic concave hull design reportedly provides a “soft and dry” ride, even in rough weather conditions.
The hull’s mirror-like gel coat was achieved through a combination of Marine Concepts’ mold design experience and fabrication techniques and Scott Bader’s materials. All the molds were made from Scott Bader’s matched tooling system, including trademarked Crystic14PA tooling gel coat, a vinyl ester/dicyclopentadiene (DCPD) skin coat and VE679PA and 474PA tooling resins. The deck and hull were made entirely from Crystic products, including Crystic LS31PA isophthalic polyester/neopentylglycol (iso/npg) brush-on gel coat. Above the waterline, a barrier coat, Crystic Crestacoat 5000PA, was applied immediately behind the Crystic LS31PA gel coat; the barrier coat improves the surface finish and, according to the company, it reduces gel coat microcracking. Plus, Marine Concepts opted to bond all stringers and bulkheads with Crystic Crestomer 1152PA structural adhesive, and cores were bonded using Crestomer 1196PA adhesive. According to Scott Bader, the practice of bonding bulkheads rather than wet overlaminating has been proven by boatbuilders to significantly reduce bulkhead print-through in the hull while also reducing weight and build times. After demolding, the hull received only a proprietary gel coat polish.
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