JEC COMPOSITES MAGAZINE - Issue #51 - September 2009 - 36

FEATURE “Marine” A unique hydroplane inshore powerboat Team 21, based in Lowestoft, East England, design, build and race inshore powerboats. For the 2009 racing season, they replaced their wooden racing craft with a newly designed Newace© fibreglass model which has a unique composite construction – the backup resin, the barrier coat and the structural adhesives used are all based on urethane acrylate chemistry. owered by a 400cc (33hp) Outboard Stock Yamoto engine (OSY400 racing class), these small one-man powerboats are approximately 3.5 metres long by 1.5 meter wide, and reach speeds of up to 61 knots. Team 21 are currently top of the OSY400-class British National Championship for 2009. They have already raced in this new FRP composite powerboat, made almost entirely from Scott Bader’s urethane acrylate technology Crystic® products. P Fig. 1: The Crystic® LS 88PA gelcoat surface finish is enhanced by using Crystic® Crestacoat 5000PA barriercoat and Crystic® VE 679PA skincoat, which reduces cracking and provides a long-term, high-quality gelcoat surface. section. The hull laminate structure uses a Crystic VE 679PA vinyl ester/ DCPD skincoat on top of the backup resin, which improves the aesthetics of the gelcoated outer surface by reducing print-through and providing blistering resistance. Directly behind the Crystic LS 88PA marine grade gelcoat is a Crystic Crestacoat 5000PA barriercoat, another urethane acrylate-based product, which is applied to help reduce drag by producing an ultra-smooth surface finish. The barriercoat also provides greater laminate flexibility to help prevent gelcoat cracking. This combination of matched gelcoat, barriercoat and skincoat laminate construction is recommended by Scott Bader as the optimum solution for a long-term high-quality surface finish, particularly in demanding applications and where aesthetics are critical. While there is considerable design freedom in this powerboat racing class, the hull design has to meet the specifications defined by the RYA (Royal Yachting Association) for UK racing and the UIM (Union Internationale Motonautique) for International racing. Innovative composite hull The unique Newace© composite hull has a hydroplane design built to withstand the very high flexural and impact forces experienced during the demanding racing conditions, and has extremely good fatigue resistance. The backup resin is Crestapol® 1220, a urethane acrylate polyester blend resin selected for its tough, very high mechanical properties. According to Scott Bader test data, Crestapol 1220 has over 50% higher shear strength than a conventional ortho- or isounsaturated polyester resin and more than six times the load fatigue performance. High-density PVC foam is used in the underside of the hull. Kevlar twill-weave cloth and woven glass fibre matting are used for reinforcement. Kevlar is a high tensile strength and high modulus composite fabric that is ideal where maximum strength and minimal weight are critical. Plywood, glass mat and Kevlar cloth were used around the cockpit Fig. 2: Team 21 in action, winning their National Championship race earlier this year in the UK with their new lightweight composite Newace© design OSY 400 class inshore powerboat built from Scott Bader Crystic® products. Fig. 3: Sponsored by Scott Bader, the new Team 21 OSY 400 class inshore powerboat is made almost entirely from urethane acrylatebased Crystic® products. Weight-saving adhesives An additional construction feature of the new Newace© composite hull is the use of Crystic Crestomer® structural adhesives to help reduce weight. Areas of the hull and cockpit, as well as the deck-to-hull joint, were bonded together using 36 jec composites magazine / No51 September 2009

JEC COMPOSITES MAGAZINE - Issue #51 - September 2009

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #51 - September 2009