CompositesWorld

JAN 2016

CompositesWorld

Issue link: https://cw.epubxp.com/i/620463

Contents of this Issue

Navigation

Page 46 of 51

45 CompositesWorld.com Single-skin, Uncored Hull Technology Illustration / Karl Reque HydraSports Custom Sueños 53 Center Console Prisma Framing › Single-skin laminate "membrane" design transfers loads to low-section frames, eliminating need for core in the hull. › Low-section frames can be easily moved and re-engineered to accommodate customized features requested by customers. › FEA-identifed areas of high hull defection are mitigated by more closely spacing frame members to reduce free panel size. hull structure," explains Lewit. "You get rid of the core, which adds weight and can break and absorb water." Bergstrom explains that, unlike the Navy combatant boat designs, the Sueños 53 design does not include a suspended sole for shock mitigation: "Tose RIBs are much smaller than our vessel, and to suspend the sole on a vessel of this size would have required signifcant structural changes to the sides, so we opted not to go that route." Also, the Navy boats used Structural Composites' gel coat replacement, trademarked Sharkskin, a tough and fexible elastomeric coating that can handle any hull fexion. Again, that wasn't an option for HydraSports Custom, says Bergstrom: "We're marketing a high-end product, and had to present a glossy gel-coated hull for customers." (Lewit's company has developed a new gel coat solution that it calls CoCure for high-end applications.) Using FEA, Lewit and Reichard worked on developing the thinnest possible hull laminate skin that was still rigid enough to handle the larger vessel's weight. Says Lewit, "Te design problem is thickness-sensitive. It's a challenge to develop a fexible membrane hull laminate with sufcient load-bearing strength for the application." Te process also required design and location of the hull's low- section frames, which would be provided under the trade name Prisma to HydraSports Custom by Lewit's and Reichard's second company, Compsys Inc. (Melbourne, FL, US). Prisma frames are lightweight polyurethane foam covered with a reinforcing fabric. Hull & transom are uncored laminate Transom features single transverse frame with PVC foam reinforcement HULL/FRAME ASSEMBLY Low-section framing absorbs loads from uncored hull Transom for engine support (see hull/ frame at right) FRAME DETAIL Low-section frame spacing reduced to avoid gel coat cracking due to hull panel fexion - Vessel powered by four outboard engines Outboard engines enable full "walk- around" deck design Taller (≤1.2m) stringers support the sole (deck)

Articles in this issue

Links on this page

Archives of this issue

view archives of CompositesWorld - JAN 2016