BUILDER PROFILE | SYNERGY MARINE
he mould is everything. T Preparation is with release d, and coated cleaned, polishe first time. h, is a perfect fin ve gi to ts en ag
As soon as the gelcoat is set, an d better while it is still tacky, the first layer of unidirectional glass mat is ap plied
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Several layers of mesh and membranes ar e then added to aid the flow of resi n around the la yers of glass and m at.
Building an OK Dinghy - The Synergy Way was changing from a plywood sandwich construction to a fully glass FRP construction. The boats are far more robust whilst being lighter.” But the Synergy build process is largely the same as it has always been. “New and improved resins and materials have come along which have helped improve the finish of the boats. We made a conscious decision to not gelcoat our boats due to the difficulties of adhesion between the polyester gelcoat and the epoxy resin. It can be done but having repaired lots of epoxy gelcoated boats from various manufacturers we decided that we didn’t want the hassle. Spray painting worked better for our boats.” “Then, when we started building International Cadet dinghies we had to use polyester resin due to the class rules. Rather than hand layup the boats we started infusing the boats as there was less mess and smell. We found that we could produce a very good quality infused boat that was NOVEMBER 2018 • www.okdia.org
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stiffer and lighter with a polyester gelcoat. We built a couple of test OK hulls using the same materials and the results were very good. For a boat that doesn’t have high rig loads I’d say that the polyester infused boats are every bit as good as the epoxy boats and cheaper. But we still offer both construction methods.” He says the main advantage of the infusion process is that they can control materials, particularly resin, very accurately. “One of the issues with traditional polyester boats is that there is a high resin to glass ratio. Polyester resin is very stiff when cured. But when a panel flexes the resin and glass gradually degrade as the fibres fracture. Hence the reason polyester boats can go soft over time. Epoxy is far more resilient to flexing so the glass fibres don’t break. With infusion we are using a low ratio of resin to glass, so the laminate is thinner and less prone to fatigue. So the boats will remain far stiffer than has traditionally been the case for polyester boats. “ 15