We offer a unique prospective and an in-depth approach when it comes to choosing a shipyard that will be tasked with building a multi-million asset that turns your dream into a reality. As a passionate team of designers, engineers, captains, surveyors and production line professionals, we take pride and thrive in every day challenges of building and delivering the perfect yacht; a yacht that will be unique in quality, craftsmanship, performance and durability. A yacht that will stand the test of time. We go above and beyond to deliver this.
Working solely for the client, with their best interests and requirements at the front and centre of any given situation, we are able to deliver impartial advice on what to build, which shipyard to choose, and the best way to proceed at various stages; before, during and after the construction. Intelligence, thorough planning and quality control are paramount to the success of your new yacht and her first years in the water.
Our unbiased approach cuts through the marketing noise and ensures that you are provided with an in-depth analysis of a yard’s financial stability, their building quality, delivery history and warranty reputation, as well as their unique features, selling points and advantages. Based on realistic assessments of where the risks and opportunities lie with each of the shortlisted yards and competitive offers they have put forth, we are strategically positioned, guiding your authorised regional dealer where necessary, to negotiate balanced and compelling contracts once the shipyard has been chosen.
If designed to be built in glass reinforced plastic (GRP) or a composite construction with various core materials and exotic high strength fabric the design work will first be checked and approved by Class. All resin, core material, and fabrics will need to be Class approved and the process undertaken in Class approved workshops and working conditions.
It is common for large yachts to be built as a ‘one off’ which is to say not made in a pre made mould tool. Temporary hull frames and centre line are CNC cut and set up so that the core material can be fitted and then the outside laminated before the hull is turned over for the inside laminate.
One method of making GRP yachts is to use ’resin infusion’ where by mould is sprayed with the gelcoat first and all the dry materials including the core are fitted. A large air tight bag is then fitted over the mould and a vacuum made by powerful pumps. The resin, polyester or epoxy’ is then controlled fed into the laminate and allow to dry before removing the vacuum and bag. This reduces the amount of styrene monomer in the air and workshops to a minimum and the work process is generally considered quicker.
Building yachts in wood should not be undervalued or underestimated. There may not be a large number of yachts built in this material but it is far from a dead industry and in some countries such as Turkey and Indonesia it is still thriving.
It is sometimes assumed that wooden yachts are old fashioned, expensive to make and upkeep plus there is a shortage of good timber and decent boat builders. This may be partially true but almost any production yacht will be built as a ‘plug’ in timber first before making it into the production mould. Also building a GRP yacht as a ‘one off’ of any size the temporary hull frames, centreline and deck will almost certainly be made of timber.
There is a good deal of romance and charm in the idea of building yachts and boats in wood. This may be due in part to the mystique and history of the process together with the fact that wood is a living material with personality, texture and smell.
It is generally agreed that wooden yacht building is very labour intensive so building in the traditional wood method makes it difficult to compete commercially with other materials such as GRP, Steel and aluminium. Despite this large yachts of 100 feet and above are being built. Several European shipyards specialise in this type of high end work. The 112’ yacht ‘Merry Maid’ built in 1904 was completely re-built in England from 2006 to 2008 including all new hull and deck planking. Also Turkey and Indonesia have a steady build industry making large wooden sailing yachts, Phinisi and Gullets. Several European yards have excellent experience building and restoring wooden yachts both sail and power.
Yachts can be built using the traditional carvel method (plank on frame) or more often with modern wood-epoxy, strip plank, diagonal cold moulded or a combination of these methods plus marine plywood.
The various types of wood used in traditional and modern yacht building is well documented. Oak and other hardwood was used for the keel, frames and deck beams with Teak or high quality Mahogany used for hull and deck planking. Cheaper boats were built using Pitch Pine or Larch planking much depending on the location and available timber. A large variety of type and species of wood are now available. Hard and softwoods from Europe, Africa, Asia and the Americas are widely available with well documented detailed properties, weight, durability and usage. They should be studied to see the overall advantages and properties.
The wood must be able to glue well and take a fastening. Woods such as teak or white oak are oily so tend to repel epoxy and other glues. Soft woods like pine, fir, spruce, cedar, cypress, and redwood take glue well but are less durable. These species are often found in long straight lengths and also take paint and varnish very well. Yachts are now invariably built of wood which has been ‘kiln dried’ so have a low moisture content. The wood is stable often with hull planking machined to fit and be glued well to each other such as with strip planking.
The timber should be, dry, clean and free of knots. Wood will not bend properly if there are knots of any size or awkward grain direction. Knots smaller than 8 to 10mm diameters are usually not a bother. The grain should also be as straight as possible and clear with no irregularities or twists as this will affect the strength and bending properties of the wood. The wood chosen should take and hold screws, nails and glue well.
The main keel, stem, stern post, horn timber, hull and deck frames, and hull floors will be made of a durable hardwood. These parts will be made and set up first. They may be cut from solid timber but more often laminated with glue to save space and reduce weight.
The hull can be planked by carvel method, by pre-machined strip planking, by cold moulding or a combination. Cedar is often used for strip planking as it is light and durable and glues well. The completed hull is often coated on the outside with epoxy resin and a bi-directional fibre glass cloth. The plan is to encapsulate the dry hull timbers in epoxy resin. Outside with glass cloth and epoxy resin to keep marine borers out and inside with a thinner epoxy resin to impregnate the wood to stop water getting in which can lead to rot.
The mast, boom and other spars will be hollow to reduce weight and glued in accordance to the design drawings. Sitka or Silver spruce is considered among the best timber as it is light in weight, glues well and looks good when varnished. It is expensive and often difficult to get.
Douglas fir, sometimes referred to as Oregon pine is a good alternative. It is heavier that Spruce but glues and varnishes well. European Pine is not as good but often used on small boat masts and spars.
Building in Aluminium is similar to steel but the material is much lighter in weight, more expensive to buy and more difficult to weld properly. It is easy to cut and shape but needs skill to weld as it distorts easily when heated. Welding needs to be undertaken by qualified ‘coded ‘welders. The tools used are similar to that of steel using MIG welding tools but also TIG. TIG Welding (tungsten inert gas) is an arc welding process that uses a non-consumable tungsten electrode to produce the weld. The weld area is protected from atmospheric contamination by an inert shielding gas (argon or helium). TIG welding required considerable skill and is much more difficult to achieve than MIG.
MIG wire welders (metal inert gas) have a roll or ‘spool’ of wire inside and a motor drive that pushes the wire to the gun through an umbilical. The length of this umbilical is important as if too short the main unit will need to be constantly moved. A trigger on the gun starts the power, wire, and gas shield which keeps oxygen away from then weld. A ‘ground’ clamp must be attached to the work so the electric circuit is completed. It is important that the aluminium welding work and the working area is clean and not contaminated by other work such as steel grindings or oil.
It is important to store the welding wire so it is keep it clean, dry, free of oils and preferably warm. It is best to store the wire in a box with a moisture absorbing agent, or desiccant like Activated Alumina.
The surfaces to be welded are cleaned by first wiping it with a de-greasing agent such as acetone on clean rags to remove oils and dirt. The area is then brushed with a stainless steel brush, by hand or on a power tool. The oxidation layer that forms on the surface has a much higher melting point than the aluminium that lies underneath and if it is not removed it will create problems when welding. The cleaning brush should not be used on anything other than aluminium.
Needless to say all the aluminium materials must be Class approved and documented and the welding wire must match the material used. Some recommend using 5356 for welding 5082 and 5086 aluminium alloy which is one of the standard alloys for yacht building. The 5356 is the preferred wire for use with the 5000 series aluminium because it produces stronger welds. No matter what wire you use they all must be used in combination with 100% Argon shielding gas.
Aluminium will distort when heated and the common practice is to ‘stitch weld’ in order to allow time for the welds to cool and hence minimize distortion. This means welding three or four inches and then make a break. MIG welding must also be carried out in a ‘windless’ area so the shielding argon gas is not blown away. This means no wind or fans must blow onto the area being welded.
Welding Aluminium produces ozone, nitrous gases, carbon monoxide, and carbon dioxide, and welding in a confined or poorly ventilated space or with the welding mask directly above the weld will allow inhalation of enough of these fumes to cause you respiratory distress, in the form of shortness of breath, dizziness, nausea, and coughing. All the required health and safety rules must be followed and the operated able to breathe clean uncontaminated air.
The steel hull as a whole, or a hull module, will need to be built on a level, strong foundation. This foundation may well be used to move the completed module, or completed hull, to the next stage of the build or even the complete build and then used to launch the yacht. The alignment of the base and the yacht in build needs to be checked by laser sight every few days as this is critical to the complete process.
The build of any yacht can only be executed by trained and experienced staff. Regardless of the material used the tradesmen doing the work must be skilled. They must understand the quality, process and what is to be achieved. Class will require that a welder is qualified and has the correct training and the correct tools. The hull, deck and superstructure will be ‘set up’ then full welded prior to plating. Inspection by class will probably take place at this time.
A steel hull below 130’ may be built upside down as ‘down hand’ welding is easer so more accurate than overhead, but the availability and lifting capacity of the shipyard cranes will decide what is possible. Welding will be with MIG (Metal inert Gas) which has a thin wire electrode fed by a motor to the welding head which is shielded with the gas (Mixtures of argon, carbon dioxide and oxygen are marketed for welding steels. This system of welding is faster and cooler than the old type of ‘stick welding’ or arc welding which is shielded metal arc welding (SMAW), also known as manual metal arc welding (MMAW)
For large yachts the keel sections, frames, floors, deck beams and other large parts will be assembled first and then set up on the building base aligned with the laser sight. Hull sections which include the deck may also be built ‘modular’ by individual teams and moved to the main assembly area when ready. The structure is ‘set up’ first and checked for alignment prior to full welding.
The build of the hull will progress with the hull frames and stringers fitted along with floors and the main structural bulkheads. Integral tanks, those which use parts of the outside hull as part of the tank, will also be built in accordance to the class approved drawings. Again the structure is checked for alignment prior to full welding. The ‘full weld sequence’ will also be planned and executed in accordance to the drawings, build instructions and speciation.
The foundations for the main engines, generators and large items of machinery will also be built and installed at this time. If a sailing yacht the mast step will be fitted along with extra stiffening for chain plates and rigging.
The hull will be plated with Class approved material, in accordance with the construction drawings and technical specification. The plate will be cut, cleaned and joints prepared with best quality yacht building techniques. The hull plating will be set up (fit up) and tack welded first. The hull plating will be full welded inside and out to welding sequence agreed with the project manager and welding foreman so as the reduce distortion and stresses. On completion of the welding all exterior hull welded will be ground flat and inspected possibly with X ray. The cleaned weld will be locally grit blasted or vacuum blasted and coated with the appropriate epoxy primer.
The build contract will ordinarily require a specific number of NDT inspections of a percentage of all welds and this will be witnessed by Class. Welds may be X rayed, tested by liquid penetrant (Dye-pen) or magnetic particle inspection (MPI) and a written report prepared. In a good weld these tests would indicate no cracks in the radiograph, show clear passage of sound through the weld and back and indicate a clear surface without the penetrant captured in cracks. MPI and advanced testing may not be available in house so will be sub contracted to a specialist. Class will normally also inspect fit up before welding. The build standard to be achieved is specified by Class. An important distinction at this stage is that the classification society is working for the yard not the owner of the yacht.
The main deck will probably be the same material as the hull but it is not uncommon for the superstructure to be constructed in a lighter material such as aluminium or GRP composite. A suitable transition joint must be made between dissimilar metals such as steel and aluminium. A number of pre-made transition joints are available from suppliers enabling the steel and aluminium to be joined without electrolysis.
The deck beams will be prepared and fitted or the hull frame and deck beam all cut and made in one piece called a ‘ring frame’. The deck beams will have additional stiffening, knees and supports and may well combine the side deck bulwark and rail capping. As with the hull the deck plating will commence and this will give great stiffness and strength to the structure even if not fully plated. The superstructure can with advantage be built off the vessel separately and partially completed at ground level prior to be being fitted. This leaves the hull open and makes work on the ‘stage one fitout’ much easier.
Our structural engineer will supervise and meticulously inspect the process, drafting detailed reports and analysis during all of the major stages of the hull construction.
The structure of the vessel must be assessed throughout the building process, all the way up to the sea trials, to ensure that risks of future faults are eliminated before the vessel becomes operational.
The hull and superstructure material and construction details will be given in the design drawings and the technical specification. The hull may be built in Steel, Aluminium, Wood or GRP composite. The deciding factors will be: the use of the yacht, speed of build, availability and cost of the material relative to the size (steel is cheaper but heavier than Aluminium or GRP). GRP yachts in excess of 200’ have been built but steel is generally used. It is strong, widely available, easily worked and repaired and not expensive. Whatever material is used it will need to be ‘Marine Grade’ and approved by Class. It is common that the designer/naval architect will supply CNC cutting files so the various parts can be accurately cut by laser or water jet making assembly precise and fast.
