The markets: Boatbuilding and marine (2020)
In the boatbuilding and marine markets, the increasing size and number of outboards per boat is driving the need for reduced weight in composite hulls and decks.
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Hinckley Yachts’ Dasher features carbon fiber/epoxy construction and electric propulsion. Source | Hinckley Yachts.
The National Marine Manufacturers Assn. (NMMA, Chicago, Ill., U.S.) reported in 2019 that unit sales of new powerboats increased 4% in 2018, reaching 280,000, the highest total since 2007 for the U.S. recreational boating industry. NMMA predicts 3-4% growth for 2019 and noted that boat manufacturers have concentrated on new products, especially in fishing, watersports and pontoon boats. NMMA’s top trends for 2018 included:
- Wakesport boats represented the recreational boating industry’s highest growth in 2018 (9-11%), totaling 10,000 units.
- Pontoon boats increased 4-6%, to 58,000 units, valued for their versatility in use for fishing to cruising to watersports.
- Personal watercraft continued to stay strong, with an entry-level price, growing by 6-8% to 68,000 units.
The trends for larger production boats powered by outboard engines (compared to inboard diesel engines), as well as increasing use of carbon fiber (CF), epoxy resin and 3D printing continue. In the Jan. 2019 forecast by Boating Industry, Ryan Kloppe, director of sales at Statistical Surveys Inc., said his company was expanding its 16- to 40-foot reporting category to 45 feet. “People are building bigger boats,” he said, noting continued growth in larger boats powered by outboards for fishing and cruising.
Examples of outboard-powered boats — more than 40 feet long, each with at least three or four engines clamped to the transom — include Scout Boats’ (Summerville, S.C., U.S.) 530 LXF (53 feet), HCB Yachts’ (Vonore, Tenn., U.S.) 53-foot Sueños and 65-foot Estrella center consoles, and Midnight Express’ (Miami, Fla., U.S.) 60-foot Pied-A-Mer. Outboards are chosen for their light weight and reduced requirement for systems and space inside the hull. As with cars, space in boats is at a premium.
One boat trend that might appeal to a younger market is electrification.
The increasing size and number of outboards per boat is driving the need for reduced weight in composite hulls and decks, but without sacrificing performance. The latter means not only long-term durability in the water but higher speeds and resistance to wave-slamming loads, as well as heat resistance beneath dark paint colors, which continue to be popular. Carbon fiber and epoxy provide a particularly effective combination, and, in fact, are used on Scout’s 530 LXF and 420 LXF models, manufactured via resin infusion. Carbon fiber is also used in HCB’s Estrella. Hinckley Yachts (Southwest Harbor, Maine, U.S.), renowned luxury production builder and longtime veteran of resin infusion, has begun switching all of its sailing and power models to epoxy, while its 40-foot Sport Boat models and Dasher fully electric motor yacht feature CF/epoxy construction. Note, however, that these brands represent the high end of the market. Boats priced in the middle of the market typically use glass fiber and vinyl ester resin, though resin infusion has become much more common. Polyester resin is still used for the lowest-priced boats. Carbon fiber is creeping into medium-priced boats, used to cap hull stringers and in accessories like hard tops where owners are willing to pay for higher-priced options.
Price, however, is an issue, as explained by an Ohio respondent to Boating Industry’s survey: “The industry has priced product out of reach for the middle-class boater. The guy who bought the ‘starter’ boat and allowed boat builders and motor companies to grow has been removed from the market. We need to target a younger crowd with [affordable] price point boating products.”
One boat trend that might appeal to a younger market is electrification. “As hybrid gas/electric cars such as Tesla and Prius have grown in popularity and become more practical options for mainstream consumers, boat manufacturers have begun to follow suit,” explains a 2019 guide for buyers on Boattrader.com. Though electric-drive boats have been heralded as “the future” for some time, and were actually the norm for powerboats before the 1930s, their advance into today’s market has been slow. However, with battery and hybrid power technologies dropping in cost thanks to the auto industry’s continued development, sailboats and small cruising power boats are being introduced that eliminate the tanks, fumes and environmental impact of fossil fuels. Examples include Hinckley’s Dasher, the 12-meter long, 16-passenger Soel Cat 12 by Soel Yachts (Delft, Netherlands), the 7.47-meter 740 Mirage Air center console by Frauscher (Gmunden, Austria), Q Yachts’ (Finland) Q30 tender and the Secret 33 water taxi, ElectraCraft’s (Westlake Village, Calif., U.S.) electric pontoon boats and Greenline Yachts’ (Begunje, Slovenia) line-up of electric and hybrid models 10 to 21 meters long. This trend is expected to gain more momentum as reliable cruising range and speed are established (note the new electric boat speed record of 88.6 mph set in July 2019). Most docks already have electrical power for recharging.
A project reiterating this point is the all-composite hydrofoiling watercraft developed by SeaBubbles (Paris, France) with support from composites fabricator Décision SA (Ecublens, Switzerland) and Sicomin Epoxy Systems (Chateauneuf les Martigues, France). This eco-conscious taxi transport solution for the world’s urban waterways is based on a hydrofoil design that allows the watercraft to glide silently above the water when it exceeds 12 kilometers per hour, which reduces drag 30-40%. A clean-charging electric drive system converts solar, wind and water power so the vessel does not generate any CO2 emissions. SeaBubbles began testing the craft on the River Seine in Paris in September 2019; if all goes well, commercial service could begin in Paris in 2020. The technology’s makers hope to spread SeaBubbles to more than 50 waterway-rich cities worldwide.
While printing boat structures is just at its beginning, the move toward 3D-printed molds is continuing to gain momentum.
Another trend is the growing use of 3D printing in marine. Already, high-end yachts are using 3D-printed parts. For example, Hinckley’s Dasher electric features a stylish console supported by six parts that nest and interlock, 3D printed in partnership with the University of Maine’s Advanced Structures & Composites Center (UMaine, Orono, Maine, U.S.). According to Hinckley’s director of engineering Scott Bryant, the tight-tolerance pieces would have been difficult to produce with traditional molded fiberglass reinforced plastic (FRP) due to resin shrinkage. Now, the UMaine Composites Center boasts the world’s largest prototype polymer 3D printer, largest solid 3D-printed object and largest 3D-printed boat. The 3D printer, called MasterPrint and produced by Ingersoll Machine Tools (Rockford, Ill., U.S.) in partnership with Oak Ridge National Laboratory (Oak Ridge, Tenn., U.S.), can print objects as long as 100 feet by 22 feet wide by 10 feet high, depositing 500 pounds of material per hour. UMaine's claim on the largest 3D-printed boat is its 25-foot, 5,000-pound 3Dirigo, being tested in the Alfond W2 Ocean Engineering Laboratory, an offshore model testing facility with wave basin.
The UMaine Composites Center’s 3Dirigo is a 25-foot, 5,000-pound 3D-printed composite boat. Source | UMaine
The world’s first 3D-printed boat was a 6.5-meter-long and 3-meter-wide Mini 650 sailing yacht, designed by Livrea Yachts (Palermo, Italy) and built by sister company Ocore in partnership with Autodesk (San Rafael, CA, US), Lehvoss Group (Hamburg, Germany) and Kuka Robotics (Augsburg, Germany). Ocore is using fused deposition modeling (FDM) via a mounted extrusion head on a 2.5-meter-tall Kuka robot. The head melts compounded 25% chopped carbon fiber-reinforced polyamide (PA, or nylon) pellets and deposits 0.6-millimeter-thick layers to form the hull, rudders and other components. The hull is printed in sections called isogrids, which resemble an aerospace skin-stringer design, with a CFRP corrugation between two CFRP skins. The isogrids are joined with structural adhesive and sheathed with skins of carbon fabric. Advantages claimed include a hull built in just days, enabling the team to print different hulls, analyze the speed forecast and identify the optimal shape.
While printing boat structures is just at its beginning, the move toward 3D-printed molds is continuing to gain momentum. Projects completed include a boat hull pattern by Marine Concepts (Cape Coral, Fla., U.S.) and a 10.4-meter-long hull construction mold by Xplora Yachts (Kirkland, Wash., U.S.). The Marine Concepts pattern was a collaborative proof-of-concept project with Thermwood Corp. (Dale, Ind., U.S.) and custom compounder Techmer PM (Clinton, Tenn., U.S.). The pattern was 3D-printed slightly oversized, over roughly 30 hours, and subsequently trimmed to final size and shape, using Thermwood’s trademarked Large-Scale Additive Manufacturing (LSAM) system. The printed material was Techmer’s trademarked Electra l ABS LT1 3DP. The final tool was printed in six sections, four major center sections with walls approximately 38 millimeters thick and a solid printed transom and bow. Sections were pinned and bonded together using a Lord Corp. (Cary, N.C., U.S.) multicomponent urethane adhesive. The assembled pattern was then machined as a single piece on the same Thermwood system in about 50 hours. The entire print, assembly and trim process reportedly required fewer than 10 working days. The pattern was subsequently used to pull a fully functional production hull mold made with conventional fiberglass reinforced plastic (FRP) molding methods.
Future molds may be printed in thermoset composites, using the new Reactive Additive Manufacturing (RAM) machine.
The Xplora Yachts hull construction mold was 3D-printed start to finish, in partnership with Oak Ridge National Laboratory (ORNL, Oak Ridge, Tenn., U.S.) using its Big Area Additive Manufacturing (BAAM) machine, manufactured by Cincinnati Inc. (Harrison, Ohio, U.s.). Although three mold sections could be printed simultaneously in 12 hours, all 12 sections of the mold were printed over a five-day period, using 2,495 kilograms of 20% chopped carbon fiber/ABS Electrafil J-1200 from Techmer PM at $11/kilogram for a total material cost of $27,500. The sections were printed with an extra 3.8 millimeters of material which was later machined to a smooth surface. Rods were assembled cross- and length-wise to build the sections with Ashland’s (Dublin, Ohio, U.S.) Pliogrip Plastic Repair 10 epoxy applied to the seams. Designed for ABS, the epoxy adhesive’s 60-minute cure time allowed alignment adjustments during assembly. Assembly was completed in three hours and the adhesive cured within 24 hours. A Faro (Lake Mary, Fla., U.S.) laser-tracking system was used to compare the mold surface to original CAD data and showed an average deviation of less than 1.27 millimeters. After being sanded and coated with tooling gelcoat and mold release, the mold was used to resin infuse a prototype E-glass and Kevlar foam-cored hull.
Future molds may be printed in thermoset composites, however, using the new Reactive Additive Manufacturing (RAM) machine, developed by Magnum Venus Products (MVP, Knoxville, Tenn., U.S.) in collaboration with Polynt Composites (Carpentersville, Ill., U.S.) and ORNL. Unveiled in Sept. 2019 as the world’s first large-scale thermoset composite additive manufacturing system, the RAM prints in a build envelope of 8 feet by 16 feet by 3.5 feet using Polynt Reactive Deposition PRD-1520 print media that cures at ambient temperature without UV activation. This technology is aimed at low-cost fixtures, thermoforming tools and autoclave molds, as well as a wider range of applications that require higher thermal properties afforded by thermoset polymers.
MVP’s RAM system. Source | Magnum Venus Products
The RAM system includes the large print platform and a floor-mounted MVP pumping system, with only the printhead mounted onto the computer-controlled gantry. The pumping system accurately measures and meters the short glass fiber-reinforced vinyl ester resin and peroxide initiator into a static mixer in the printhead. The mixed resin is then extruded through a nozzle, similar to most fused deposition modeling (FDM) systems. Print speed is roughly 1.2 m/s using a 1.2-millimeter diameter nozzle. RAM reportedly can achieve FDM-scale features while still delivering a high output of almost 7 kg/hr (15 lb/hr).
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