Yachts are known to be a luxury item, often owned by the wealthy, with price tags well in the millions. If you are wondering how yachts are made, and why so many people envy those who have them, you are not alone. Prior to 1950, steel and wood were the commonly used materials, but there are many materials used in modern yacht designs. Let’s take a look.
Although less common now, wooden hulls are still available if that is what you prefer. However, the most commonly base material used in new yacht construction is fiberglass. This is because fiberglass can be molded as needed, it is tough and offers many possibilities.
Some yacht construction uses fiberglass liners for lining inside of the hull to provide a permanent attachment and more stability to the structure. It adds more strength and joins hull sides and stringers to reduce vibration, and increases the yachts lifespan. Fiberglass liners also allow more stability to the platform, always important.
Cored Fiberglass Structures
Using cored constructions using fiberglass hull and deck elements provides additional benefits, such as increasing strength to weight ratio, makes the structure lighter, and helps with vibration absorption, and acoustical and thermal insulation.
However, cored constructions require materials which are more expensive and skills or application processes are higher. Although more expensive, many consider the quality to outweigh the cost. When it comes to safety, there are designs that use a solid laminate between the cored laminate and the through-hull location. This provides the best of both.
Core materials may include:
- Balsa – Provides superior strength and compression, harder to work than foam.
- Coremat – Provides stiffness while cosmetically insulating larger flat surfaces.
- Aluminum – Lowers risk of water intrusion, increases reliability of hardware.
- Plywood – Used for providing efficient holding of screw-type fasteners.
When it comes to laminating, professionals hand laminate various components to get the best resin-to-glass ratio for the design. Applications may use:
- Woven cloth
- Uni-directional knitted cloth
- Bi-directional knitted cloth
- Chopped strand matt
It is common for hulls to use a resin coating, such as vinyleter resin for adding a protective layer to the hull under the water line. This helps prevent water migrating into the laminated structure. It also eliminates osmotic blistering. Resin coating provides the following benefits:
Lowers exotherm to increase cosmetics
Gelcoat is used for protecting fiberglass laminates, while providing a cosmetic finish. It helps eliminate deterioration, giving it ultra-violet protection. Gelcoat acts as a pigment resinous surface with low porosity.
A spray gun is commonly used for applying gel coat to prepared molds, with a 20-25 mil thickness. If the layer is too thin, it will not provide the needed protection, but to thick and it becomes brittle.