how to build a catamaran free plans

DIY Cruising Catamaran: Complete Building Guide

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A brand-new cruising catamaran can set you back a hefty amount of money. However, a DIY cruising catamaran provides a more affordable way to own your own boat. While building a large boat can be an extremely challenging and time-consuming experience, nothing beats the pleasure of bringing your own boat to life. 

To build a DIY cruising catamaran, buy good design plans, determine your budget and find a working space. Next, choose your hull material, buy supplies and start building the mast beam. Build and sheathe the hull, install bulkheads, the interior, and finally, launch the catamaran boat.

In this article, you will find a complete guide to building your own catamaran. You will also find detailed information on why you may want to consider building your catamaran and approximately how much this project would cost. Finally, we will explore the advantages and disadvantages of building a catamaran from scratch.

Why You Might Want To Build Your Own Catamaran

Most people might think that purchasing a used boat to repair and fix it up would be cheaper than a DIY cruising catamaran. But while building your own catamaran could be an enormous undertaking, it also comes with many advantages over buying something used. 

Other than the unique opportunity to create beautiful memories and experiences while cruising, sailing, and exploring beautiful coastlines, there are a number of benefits that come along with the DIY approach.  

Knowing Your Boat

Building your own catamaran provides you with intimate knowledge of your boat. You will know every corner, including where to find every bolt, wire, bulkhead, rib, hose, and support as you installed them yourself. This knowledge will enhance your confidence while at sea since you will have entrusted your life to a boat whose history you are aware of and deeply connected to.

Pride of Ownership

The satisfaction you get from crafting something with your own hands is immense. As a result, the knowledge that you built your boat from scratch will fill you with absolute pride and an immense sense of achievement. Furthermore, as an owner-builder, you get to keep and enjoy the boat for as many years as you wish.

Substantial Cost Savings

Building your catamaran will work out cheaper than buying a new or even gently used boat. Though you will likely require some additional labor since doing some things will require an extra pair of hands, if you are particularly good at DIY, you will save a significant amount of money on labor costs as a whole. 

Freedom To Create Your Own Designs

If you decide to buy a catamaran boat, it might not be easy to find one that meets your unique needs. However, instead of choosing from production boats that bear traditional and outdated designs, you can come up with an ultra-modern design or style for your catamaran. You also get to pick your layout, size, and equipment based on your taste and budget.

Great Learning Experience

Building your own boat will help you pick up numerous skills that will come in handy later when sailing your boat. As much as you might still require an expert to help you with specialized skills like carpentry or wiring, your new skills will serve you well. This will also be beneficial when it comes to your boat’s maintenance and fixing things for yourself. 

What To Look For in Catamaran Boat Designs

When deciding on the type of catamaran boat to build, you may want to choose a design that’s simple and easy to build. This is because doing so will allow you to spend a shorter time building the boat. 

You also need to have a set of requirements to guide you in choosing your design or what you might call an ideal cruising catamaran wish list. This is essential because, ultimately, you want to build a boat that offers outstanding qualities such as:

• Delivers good speed
• Affordable to own and operate
• Agile, strong, and easy to maintain
• Has a high resistance to capsizing
• Great for sailing and cruising
• Delivers a comfortable and easy motion underway
• Good handling ability and high performance under sail
• User-friendly embarking and disembarking
• Provides ample living and accommodation space 
• Presents a reasonable resale value

It’s worth noting that, in general, catamaran boats tend to offer a fair resale value mainly because of scarcity and the high price accorded to production models. So, if you build a well-constructed catamaran, you are bound to get a return that’s much higher than the cost of materials upon resale.

It’s also good to consider whether the design you settle on is from an established designer. This is significant because documentation of the building process is just as valuable when it comes to selling the boat.

How Much Would It Cost To Build Your Own Catamaran?

The cost of building your cruising catamaran will depend heavily on the size of the boat you plan to build and the skills you bring to the table. To give you an idea of probable costs, a professionally built 40 foot (12.1 m) long cruising catamaran could go for up to $300,000. 

Though building it yourself will undoubtedly be cheaper, most DIY boatbuilders tend to underestimate the expected costs. Your final costs should cover not only the cost of material and equipment but also the labor and time it would take to come up with the final product. 

If you were to build a 40-foot (12.1-meter) catamaran, your cost of materials would range between 20-30% of the total cost. Therefore, for $300,000 total, the boat’s materials would range between $60,000 and $90,000. The hull tends to range between 15-35% of the total build. Again, this depends on the finish and furniture.

But before you even start working on the DIY project, you will need to figure out where to do the work. If your home has ample space, then you can opt for a backyard building. But if you live in a small apartment, then you might want to consider renting a small garage at first and then move on to a boatyard later. This is one of the significant costs involved in building your multi-haul.  

What You Will Need

To get a clearer picture of how much the entire project would cost, let’s have a look at what else you will need to purchase.

• Good design plans
• Working space
• Ground tackle
• Matting and roving
• Equipment such as the engine, windows, rudders, deck fittings, mast, and rigging

In addition to the above, you also need to install plumbing and electricals. You may also want to consider going electric rather than using diesel. Not only will this drastically reduce your maintenance costs, but you get to use the regenerated power for all of your housing needs while sailing. 

Some catamaran boat designs help you save costs by advocating the use of less expensive corpus materials. Most of the material goes directly into making the boat, which means there is hardly any wastage on vacuum bagging . With this method, there are few molds and temporal building forms and fewer fillers to grind off as waste. All these factors reduce the time and cost it takes to build your catamaran boat.

That said, building a boat of any kind is a huge financial undertaking. As such, you still need to have the financial ability to keep building; otherwise, your project will stall or take much longer than anticipated. Instead of enjoying yourself and making memories cruising to faraway lands, you might end up spending all your time building a seemingly never-ending boat.

To reiterate, this project is more of a labor of love, given that it involves a tremendous amount of manual work. Calculating an hourly rate on the time spent building the boat and adding this cost to that of materials may make it seem a very pricey exercise. However, it is vital to understand that your time matters, and every hour you spend working for “free” should be included. 

With that in mind, you need to ensure that you are fully devoted to the boat construction project and are sure you want to do it before you begin. Stopping halfway because it seems like too much work would be incredibly costly.

How To Build a Catamaran

When it comes to building a cruising catamaran, you have 3 main options:

• You can buy an old boat and refurbish it.
• Purchase a bare hull plus deck molding for a home-boat building.
• Start from scratch and build everything, including the hull, on your own. 

As mentioned above, renovating an existing boat may end up being more costly than starting from scratch. To build a catamaran boat from scratch, follow the below step-by-step guide.

Prepare the Essentials

Before you jump into such a large project, there are several important aspects to consider:

• Buy your plans from an established catamaran designer. You can also get inexpensive, easy-to-build catamaran designs online.
• Get access to a large working space or build a shed . Depending on your climate, you may need to opt for climate control to avoid an excess of moisture in humid areas. 
• Decide on your choice of hull material. This could be fiberglass, aluminum, steel, wood, or ferroconcrete. 
• Start working on a bill of materials estimate. Include everything that you think you need to get a better idea of the initial costs.

Build the Mast Beam

Using wood and epoxy, cut and glue together the pieces of wood that will form the mast beam. Most of the work at this stage can occur in a garage since it involves building small parts. Still, the work could take up to 4 months, so be prepared to put in long hours.

Build the Boat Hull

Now, it’s time to build the boat’s hull. A catamaran comprises two hulls which are connected with a deck. Below is a short video showing how to build a hull mold:

This work requires a larger facility, so you might need to move out of the garage and into a boatyard. If you don’t have access to a larger workshop, consider building a shed where you can work as you do the construction. Make sure there’s enough room to fit the boat and also allow you to work comfortably. To cover the shed, you can use opaque white tarps. 

Sheathe the Hull

Get all the materials you require for this stage in the construction, such as lots of resin, fiberglass, and foam for use in the hull cores. You’ll also require matting and glass roving to sheath the hull . 

Sheathing helps to make the hull impervious to water and other marine borers. But first, you need to prepare the hull using a rotary sander. To make it as smooth as possible, use light, sweeping strokes. This is a very dusty task so be prepared to wear a facemask and safety goggles. 

Install the Bulkheads

Next is installing the plywood bulkheads . You might need to call in friends to help turn the hulls or use a crane. In this step, you will need to laminate the hull sides on the molded hull panels and bond them above the bulkheads. Ensure the bulkheads are snug and sealed in place.

Construct the Interior Structure

Over the next couple of months, the boat work will involve joining the hulls together with the beams that you had made back in the garage. Then, install the cuddy cabin, decks , and the cockpit . Soon the boat will start to take the shape of a catamaran.

Next, proceed to construct the major structural components such as stairs, hatches, mini-keels, and the interior. Then comes the work of fairing the boat, which is quite labor-intensive. 

Finally, it’s time to apply primer on the catamaran boat and start the paintwork. Before painting the boat, you will need to do additional sanding to finish off the two layers of primer as well as fill all the pinholes. Since it’s a large boat, the catamaran has lots of surface area; thus, the sanding could get extremely exhausting—mentally and physically—at this point.

The painting can take a while, too. The hulls are the easiest to paint, but the topsides, non-skid, as well as masking and prepping could seem never-ending. 

The final stretch involves working on the center bridge deck cabin and other final touches like installing the engines, electricals, and plumbing. This is also the time to fix the rudders, rigging, mast, windows, and deck fittings.

Launch Your Cruising Catamaran

After many months or years of hard work, your cruising catamaran is finally ready to test the waters. After lowering the boat into the water, check carefully in case there are leaks. If none, you can set up the sails and take your catamaran out for your first cruise. 

Below is a short video that takes you through the entire boat-building process:

If you don’t have deep pockets, don’t despair. It’s also possible to build an inexpensive catamaran boat, as shown in this post from the coastal passage .

The Pros of Building a Catamaran

Though it will be a costly endeavor, there are so many things to look forward to should you decide to build your own catamaran:

• It can be lots of fun.
• You get to have a new boat.
• It’s an excellent hobby for DIY enthusiasts.
• The effort is rewarding.
• It offers a great learning experience.
• You get the exact kind of boat you want.
• You can alter building plans and tailor the boat to suit your specific needs.
• It might be cheaper than buying a new boat.

The Cons of Building a Catamaran

Though there are a number of positive aspects to a DIY build, it is just as important to keep in mind that it won’t always be easy:

• Maintenance costs can be quite high.
• It’s both mentally and physically exhausting.
• It might require some technical know-how.
• It can take many months or even years to complete.
• It requires a lot of commitment to finish the DIY project.
• It might be challenging as well as expensive to get insurance.  
• You will spend almost all your free time building the boat. 

DIY Cruising Catamaran Tips and Tricks

If you are new to boat building, it would be a good idea to build a small boat first. This would give you a good indication as to whether you’d enjoy tackling a more extensive project like building a catamaran. Again, if you are the handy type, fixing your own electronics could also save you a significant amount of money. 

Here are more tips and tricks to get the most out of your DIY cruising catamaran:

• Lower your costs. Bring down your costs even further by sourcing for parts and supplies at marine surplus outlets, Craigslist, eBay, or wholesale suppliers. 
• Enhance your resale value. Most home-built boats are not easy to sell since they tend to be too customized. To enhance your resale value, it’s advisable to work with a standard design from a well-established naval architect.
• Follow the design instructions. Make sure to follow the designer’s instructions regarding the type of materials and tools to use during the build to avoid making costly mistakes.
• Maintain your original budget. Avoid any additional customizations once you have started building the boat. Using good plans and sticking to them ensures that your budget doesn’t spiral out of control.

Final Thoughts

Building a catamaran is about more than saving money. It’s fun, exciting, fulfilling, and can be a great learning experience. While it might take many months of back-breaking work, comparative shopping and sourcing for materials will help you save a lot of money. Still, at the end of it all, you’ll have a beautiful catamaran boat, all ready for your first cruising adventure.

However, if you have neither the time nor the energy to build your own catamaran from scratch, refurbishing an existing hull might prove faster and easier. It also works out much cheaper than buying a new boat.

Owner of CatamaranFreedom.com. A minimalist that has lived in a caravan in Sweden, 35ft Monohull in the Bahamas, and right now in his self-built Van. He just started the next adventure, to circumnavigate the world on a Catamaran!

One thought on “ DIY Cruising Catamaran: Complete Building Guide ”

Hello, I am a French Quebecer who is original, imaginative, creative and who finds that all boats and catamarans have a huge flaw and a very big lack of logic. I would have a brand new concept…. I am sending this message to any catamaran creator – designer to make those who have the opportunity and the intelligence to want to know about my innovative idea which will finally upset the market much richer. An idea that will totally change the concept of sailing, navigation and save so much worry!! All I would ask for is a small percentage of each sale of the new product. To be able to make me produce one when I have enough!! It is certain that like that, you just want to tell me: come on Mr. Lessard give us your idea but do not take your word to help me in return! But, if you are the kind of man to have only one word and maybe have a proof of your good faith if the realization of the project would make it… I will be very happy!! Giving it to everyone wouldn’t bother me either…. all I would like is to be able to find flax fiber (too expensive carbon) to be able to try to make my catamaran myself. Because not rich! Have a nice day and looking forward to having a message!!

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How To Build A Catamaran? (A Step-By-Step Guide)

Are you excited about the prospect of building your own catamaran? With a little research, planning, and the right tools, you can turn your vision into reality in no time.

In this step-by-step guide, well show you how to make the most of this incredible boatbuilding project.

From selecting the materials and planning the design to constructing the hulls and deck and outfitting the boat, well walk you through everything you need to know to build a catamaran of your own.

So, grab your tools and lets get started!

Table of Contents

Short Answer

Building a catamaran requires careful planning and a lot of patience.

The first step is to decide on the design and the materials you will use.

You will need plans for the project, along with lumber and other materials such as fiberglass and epoxy.

The next step is to build the catamaran frame, which involves cutting and fitting the wood pieces together to form the hulls and decks.

Finally, you will need to attach the decking, add the rig and sails, and finish the project with paint and varnish.

Benefits of Building a Catamaran

Building a catamaran can be a very rewarding experience.

Not only will you have the satisfaction of creating something with your own hands, but you will also have a boat that is uniquely yours.

Catamarans offer many benefits over traditional monohull boats, making them an ideal choice for those looking for a reliable and efficient ride.

These benefits include greater stability, more space, improved fuel efficiency, and greater speed.

Stability is one of the biggest advantages of catamarans.

The two hulls provide a wider base that helps to keep the boat from rocking and rolling in rough waters.

This makes for a much smoother and safer ride, even in choppy waters.

Additionally, the two hulls create an open area between them that is perfect for storing equipment, making it ideal for longer trips.

Catamarans are also more fuel efficient than monohulls.

This is because the two hulls provide lift, allowing the boat to glide through the water more easily.

This means you won’t need to use as much fuel to power your boat, allowing you to save money in the long run.

Finally, catamarans are faster than monohulls.

This is due to the increased surface area of the two hulls, which allows the boat to move more easily through the water.

This makes them ideal for those who want to travel quickly and efficiently.

Overall, building a catamaran can be a fun and rewarding experience.

With the right materials and tools, you can create a boat that is unique to you and offers many benefits over traditional monohull boats.

With the right planning and construction process, you can create a catamaran that will be the envy of your peers.

Selecting the Materials

Selecting the right materials is a crucial step in building a catamaran.

The type of material you choose will depend on the size and type of catamaran you are building, as well as your budget and experience.

Catamarans are typically constructed from wood, aluminum, or fiberglass.

Each of these materials has unique advantages, so it is important to research the pros and cons of each before making a decision.

Wood is the traditional material used to build catamarans and is often the most cost-effective option.

Wooden catamarans are strong and stable, and they can be custom-built to any size or shape.

However, wood requires a lot of maintenance and can be susceptible to rot and water damage.

Aluminum is a great option for larger catamarans, as it is lightweight and resistant to corrosion.

It is also relatively easy to work with and can be welded together to create a strong and durable structure.

However, aluminum is a more expensive material and is not as flexible as wood or fiberglass.

Fiberglass is the most popular material for building catamarans, as it is lightweight, strong, and resistant to corrosion.

Fiberglass is also relatively easy to work with and can be shaped to create unique designs.

However, fiberglass is also the most expensive option and can be difficult to repair if damaged.

Once you have selected the material, it is important to purchase the right amount for the project.

Make sure to measure the catamaran carefully and purchase enough material to account for any mistakes or waste.

It is also important to purchase high-quality materials that will last for years.

With the right materials, you can build an amazing catamaran that you will enjoy for years to come.

Planning the Design

When planning the design of your catamaran, youll need to consider a variety of factors, including the size, shape, and type of material youll be using.

Consider the size and weight of the catamaran and the type of water it will be used in.

Youll also need to think about how the catamaran will be used, such as for recreational or commercial purposes.

When it comes to the shape of the catamaran, the most common design is the two-hulled V-shape.

This shape is ideal as it offers stability and is easy to maneuver.

However, depending on the type of use, other shapes, such as the three-hulled catamaran, may be better suited.

The material you choose for your catamaran will also play a role in the design process.

Common materials used to build catamarans are wood, fiberglass, aluminum, and composites.

Each material has its own advantages and disadvantages, so its important to research and select the best material for your project.

Finally, when planning the design, youll need to consider the outfitting of the boat.

This includes items such as decking, seating, and a helm station.

Make sure to think about the type of equipment youll need for your catamaran, and consider how it will be installed.

By taking the time to plan the design of your catamaran, you can ensure that you get the best possible outcome.

Doing your research, selecting the right materials, and choosing the right outfitting will all help you create an amazing catamaran that will last for years to come.

Constructing the Hulls and Deck

Constructing the hulls and deck of a catamaran is perhaps the most important and time-consuming step in building a catamaran.

You will need to plan the design of the hulls and deck carefully to ensure that your catamaran is strong, stable, and seaworthy.

When constructing the hulls, you will need to use strong and light materials that are suitable for marine environments.

Fiberglass is a good choice for this, as it is strong and lightweight.

You will need to cut and shape the fiberglass to fit the shape of the hulls, and you will need to use a strong adhesive to bond the pieces together.

The deck of the catamaran will need to be strong and stable enough to support the weight of the passengers and cargo.

You will need to construct the deck out of marine-grade plywood, and you will need to use a strong adhesive to bond the pieces together.

You may also need to add extra support beams to the deck for added strength.

Once the hulls and deck have been constructed, you will need to sand and finish them to ensure a smooth and watertight surface.

You may need to use a sealer or primer to protect the wood and fiberglass from the elements.

Finally, you will need to attach the hulls and deck together.

This can be done with bolts, screws, or other fasteners.

You may also need to use a water-resistant sealant to ensure a watertight connection between the hulls and deck.

Outfitting the Boat

Outfitting a catamaran is an essential part of the build process.

Once the hulls and deck are constructed, you’ll need to ensure that all the necessary components are in place for a successful voyage.

This includes items such as masts, sails, rudders, and outriggers.

It is critical to ensure that the boat is outfitted with the right components for its size and purpose.

For example, if you are building a small catamaran for speed and agility, you’ll need to outfit it with a light and responsive mast and sail.

If you are building a larger craft for comfort and luxury, you’ll need to outfit it with a heavier and more resistant mast and sail.

Additionally, you’ll need to select the right outriggers and rudders for the catamaran’s size and purpose.

Outfitting a catamaran can be a complex process, and it is important to do the research and plan ahead.

Taking the time to select the right materials and components will ensure that your boat is outfitted for success.

Additionally, it is important to use quality materials and components to ensure a safe and successful voyage.

With careful planning and quality components, you can outfit your catamaran for a successful journey.

Acquiring the Right Tools

When it comes to building a catamaran, having the right tools can make all the difference.

To get started, you’ll need a variety of hand tools, including saws, drills, sanders, and screwdrivers.

You’ll also need power tools like routers, biscuit joiners, and angle grinders.

It’s also important to have safety equipment like safety glasses, ear protection, and respirators.

You’ll also need a variety of measuring tools, such as rulers, calipers, and tape measures.

Finally, you’ll need a selection of glues, adhesives, epoxies, and sealants.

With the right tools, you’ll be able to complete your catamaran project safely and efficiently.

Researching and Planning Your Build

Researching and planning your build are essential steps in the process of building a catamaran.

The first step is to become familiar with the design and construction of catamarans.

Start by researching different types of catamarans, from the small and lightweight recreational boats to the larger and more luxurious cruising vessels.

Learn about the advantages and disadvantages of the different types of catamarans and determine which type is best suited to your needs.

Once you have a good understanding of the different types of catamarans, you can begin researching the materials and tools you will need for your project.

You will need to choose the type of wood you will use for the boats hulls and deck, as well as the type of fiberglass and resin you will use for the hulls and deck.

You will also need to choose the type of engine you will use and the type of rigging and sail you will use.

Once you have selected the materials and tools you will need for your project, you will need to create a plan for the construction of your catamaran.

You will need to determine the size and shape of your boat, the types of joints you will use to construct the hulls and deck, and the type of engine and rigging you will need.

You should also plan out the sequence of construction steps, so that you can build the catamaran in the most efficient way.

Finally, you will need to research the best ways to protect your catamaran from the elements.

You will need to determine what type of paint or varnish to use on the hulls and deck, and you will need to research the most effective ways to protect your boat from the sun, wind, and water.

By taking the time to research and plan your build, you will be able to create a catamaran that is well-built, efficient, and beautiful.

With the right research and planning, you can create an amazing catamaran that will be the envy of your friends.

Final Thoughts

Building a catamaran is a rewarding experience that can be achieved with the right approach and materials.

With a clear plan, the right tools, and a good understanding of woodworking and fiberglass techniques, you can build an amazing catamaran to share with your family and friends.

So what are you waiting for? Get started on your own catamaran build today and all the rewards that come with it!

James Frami

At the age of 15, he and four other friends from his neighborhood constructed their first boat. He has been sailing for almost 30 years and has a wealth of knowledge that he wants to share with others.

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Catamaran Plans: Design, Build and Sail your own Multi-Hull Boat

Table of Contents

Why Build a Catamaran: The Benefits of Multi-Hull Boats

Building a catamaran offers many benefits over traditional monohull boats. One of the main advantages of catamarans is their stability. With two hulls instead of one, catamarans have a lower center of gravity, which makes them less likely to tip over in rough waters. This makes them ideal for families with children, or for anyone who wants to feel more secure while on the water.

Another benefit of catamarans is their increased speed and efficiency. The two hulls of a catamaran can displace more water than a single hull, which means they can move through the water faster and with less resistance. This makes them ideal for racing or for anyone who wants to cover more ground in less time. Additionally, Catamarans are also known for their space, as the twin-hull design provides more room for living and storage than a monohull.

Catamarans also offer more flexibility in terms of design. The two hulls of a catamaran can be configured in many different ways, which allows for a wide range of customization options. For example, one hull can be used for sleeping quarters, while the other can be used for storage or as a cockpit. This makes catamarans ideal for long-term cruising or for anyone who wants to create a unique and personalized boat.

Finally, catamarans are also more environmentally friendly than monohulls. Because they are more efficient, they can move through the water with less fuel consumption, which reduces their carbon footprint. Additionally, many catamaran designs incorporate solar panels and other renewable energy sources, which makes them ideal for anyone who wants to minimize their environmental impact while enjoying the water.

Designing Your Own Catamaran: Tips and Tricks

Designing your own catamaran can be a challenging but rewarding experience. Before you begin, it’s important to consider your needs and goals for the boat. Are you planning to use it for racing, cruising, or a combination of both? How many people will be on board? What kind of conditions will you be sailing in? Answering these questions will help you to determine the size, shape, and features of your catamaran.

One important tip when designing your catamaran is to keep it simple. While it can be tempting to add a lot of bells and whistles, the more complex your design, the more difficult and expensive it will be to build and maintain. Instead, focus on creating a functional and efficient boat that meets your needs.

Another tip is to take into account the materials you will be using. Different materials have different properties and costs, so it’s important to choose the right ones for your design. For example, wood is a traditional and affordable material, but it requires more maintenance than fiberglass. On the other hand, composites materials are more expensive but offer great weight to strength ratio.

Finally, it’s important to consult with experts and professionals during the design process. There are many resources available, such as online forums, books, and classes, that can help you to learn more about catamaran design and construction. Additionally, you should consider consulting with naval architects, boat builders, and other experts who can offer guidance and feedback on your design. They can help you to refine your ideas and ensure that your boat is safe and seaworthy.

Materials and Tools Needed for Building a Catamaran

Building a catamaran requires a variety of materials and tools. The materials you will need will depend on the design of your catamaran and the type of construction you choose. Common materials used in catamaran construction include wood, fiberglass, composites, aluminum, and PVC. Each material has its own unique properties and benefits, so it’s important to choose the right one for your project.

When it comes to tools, you will need a basic set of hand and power tools to complete your catamaran project. These include saws, drills, sanders, and other tools that are commonly used in woodworking or metalworking. Additionally, you will need specialized tools such as a router, a band saw, and a vacuum bagging system if you are building with composites materials.

In addition to the above tools, you will also need safety gear, such as goggles, respirators, and ear protection. Building a catamaran can be a challenging and time-consuming process, so it’s important to take the necessary precautions to protect yourself and others. Additionally, it’s important to have a well-ventilated workspace, as some of the materials and chemicals used in catamaran construction can be harmful if inhaled.

Common Mistakes to Avoid When Building a Catamaran

Building a catamaran can be a complex and challenging process, and it’s easy to make mistakes if you’re not careful. Here are some common mistakes to avoid when building a catamaran:

One of the most common mistakes is not properly planning and designing your catamaran. This can lead to problems later on in the construction process, such as not having enough room for your intended use or not being able to fit certain components. It is important to take the time to carefully plan and design your catamaran, taking into account your needs, goals and the materials you will be using.

Another common mistake is not properly preparing your materials. This can include not properly storing or protecting the materials from the elements, or not properly cutting or shaping the materials before assembly. Proper preparation of materials is essential to ensure that your catamaran is strong and durable.

A third mistake is not using the right tools or not using them properly. This can lead to problems such as not being able to cut or shape the materials correctly, or not being able to assemble the boat properly. It’s important to research and invest in the right tools for the job, and to learn how to use them properly before starting the construction process.

Another common mistake is not properly securing and aligning the components during assembly. This can lead to problems such as leaks, or the boat being unstable on the water. It’s important to take your time and to work carefully to ensure that everything is properly aligned and secured.

Finally, not following safety guidelines is a mistake that should be avoided. This can include not wearing protective gear, not having proper ventilation, or not taking the necessary precautions to protect yourself and others. Building a catamaran can be a challenging process, but it’s important to prioritize safety to prevent accidents or injuries.

After completing the construction of your catamaran, there are several important steps to take before launching it. These include finishing the exterior and interior of the boat, and performing necessary safety checks.

Finishing and Launching Your Catamaran

Finishing the exterior of your catamaran involves tasks such as painting, varnishing, or applying gel coat. This step is important to protect the boat from the elements and give it a professional look. It’s important to use the right type of paint or finish for the materials you used in the construction, and to follow the manufacturer’s instructions.

Similarly, finishing the interior of your catamaran involves tasks such as installing cabinetry, flooring, and other finishing touches. This step is important to make the boat more comfortable and functional. You can add amenities such as a kitchen, a bathroom, and a sleeping area.

After the finishing is done, it’s important to perform safety checks on your catamaran before launching. This includes checking the boat’s systems such as electrical, plumbing, and navigation. You should also check that all the safety equipment is in place and working properly. This includes life jackets, flares, and fire extinguishers.

Once all the necessary steps are completed, you will be ready to launch your catamaran. Launching a catamaran is a complex process that requires coordination between the boat owner, the marina, and other professionals. The boat should be launched in a protected area with calm waters, and with the help of a crane or a trailer. It’s important to have a plan in place for launching and to be aware of the local laws and regulations.

Finally, after the catamaran is launched, it’s important to test the boat and make any necessary adjustments before taking it out on the water. This includes testing the systems, checking for leaks and making sure that the boat is stable on the water. After this, you can finally enjoy your new catamaran!

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Time For a Catamaran Adventure

Isn't Time For Yours?

Building Your Own Catamaran

Building your own catamaran is another option to getting into your own boat. In this page we will go over the advantages, considerations, and a detailed history and journal of our boat-building adventure with Light Wave . We hope this will give you a clear picture of what lies ahead if you go this route, including:

• Construction methods
• 9 essential design features
• Review of the four leading catamaran designers for home builders
• Construction times
• Budget: How much did it cost to build a basic cruising catamaran?
• Layout of our catamaran, LightWave , and lots of pictures
• Carllie’s article from September 2000 Multihulls Magazine: “The Boat Builder’s Wife “
• Equipment outfitting
• Radio and communication outfitting
• Dinghy selection and considerations
• Having a boat custom-built for you

Because of the huge dollars needed to buy a new or even a used catamaran, we would never have gotten a catamaran if we hadn’t built it ourselves.

Let’s start by saying that building any type of larger boat, especially a catamaran, can be one of the most intellectually and physically challenging things you will ever do.

It has been said that building a large boat is the closest a man can come to giving birth to a baby. In other words there is going to some discomfort and pain along the way; you will question yourself on whether this was such a good idea; it’s very difficult to reverse the decision; and though friends will support you, you will be on your own most of the time with your significant other if he/she is game.

Know your boat

You will intimately know every part of your boat. You will know where every wire, hose, bolt, bulkhead, rib, and support is because you installed them!

Pride of ownership

We have often thought what it would be like to just buy a boat from a manufacturer, and know that while owners who have spent a lot of cash (or future life to pay off the lien) their often possessive and competing-with-the Joneses could not begin to compare to our quiet glow of happiness and akinship we feel with Light Wave .

Our boat is like part of the family. So much time was spent on her that we have a major emotional investment. Every time we see our vessel – from a distance at anchor or approaching her in our marina, we say, “What a pretty boat! I can’t believe we built it!” Then that sense of accomplishment settles back in and we feel we have indeed earned the privilege of all of the beautiful experiences we have had sailing, cruising, exploring the beautiful BC Coast and much further a field (or should we say “an ocean”?).

You will be able to pay for the materials as you go and “donate” your time to the cause.

Get a newer design

Many of the production boats that are out there are designs of many years ago because the manufactures have to recoup their capital investment on the mold and production setup. When you build your own you have much newer designs to draw from.

Details on Our Boat Building Adventure

We had sailed our first boat Wave Dancer for five years and had many adventures on the British Columbia coast. In May 1996, I had just returned from a little one-week solo trip in the Gulf Islands of BC when I bought the book, The Cruising Multihull by Chris White (Future link to book review on our web site).

This is the book that got me going (Carllie was not yet convinced). I must have read it a half dozen times over the next 6 months, each time becoming more convinced that this was the way to go for our next boat. It was really still pre-internet web site days so I wrote to all the designers that were listed in the back of the book. Over the next several weeks packages of information started appearing in the mailbox (there is just something about getting packages in the mail – I guess it’s the anticipation). I would pour over these preliminary printed pages with pictures and accommodation layouts. Next, I put a few dollars down to buy the information packages and study plans from the top prospects.

I waited patiently for the study plans. It was like the night before Christmas when I was kid. Oooh the wait! Finally they came, and again I carefully scrutinized the next level of detail. Things were getting a little more serious. The top contenders were:

• Richard Woods
• Chris White
• James Wharram

Click here to read my comments and reviews on their catamaran designs as well as those of Jeff Schionning.

I remember initially drooling over the Atlantic 42 by Chris White, still one of my favorite designs. It seemed to be so seaworthy (by the way if I run into about $800,000 USD any time soon, I am going to buy an Atlantic 55). The most important piece of advice that came out of the material was from Richard Woods:

“Build the smallest boat you‘d be happy with it.”

Axiom #1: The hours to build a catamaran is in almost in direct proportion to its weight.

Which brings us to Axiom #2:

Axiom #2: It takes about 1 hour to create 1 pound of finished boat.

In our case we spent 3,500 hours ( click here for full details on the construction hours ) to build a 4,000 lb. boat (just a little less than 0.9 hours per pound). If a boat’s empty weight is 8,000 lbs., it will probably take about 6,000 hours to build.

When you think about it, you can only mix and handle so much material per hour. More boat weight, more material, more hours. Sure there are some economies of scale on a bigger boat, but usually the systems become more complex and these take longer to install.

This decision process took 8 months and I figured we’d launch in 6 months. It was now January of 1997. Little did we know it would be 26 months and 3,500 hours between the two of us until we launched on June 5, 1999. We ordered the full plans and we were off and running.

We were ready to build, but where would we start the process? First of all, we live in a tiny 480 sq. ft. apartment in Vancouver. Back-yard building wasn’t exactly an option so I found a small garage nearby that we rented for 5 months.

After about 4 months in the garage, I had made all the small parts and it was time to build the hulls. This meant that we had to go larger facilities. We found space at Shelter Island Marina and Boatyard in Richmond. This is the biggest boat yard in the Vancouver area with dozens of commercial and private projects, big and small, under way.

We were out of money by then, so we sold our first boat so we could buy resin and fiberglass. It was a traumatic time as we said goodbye to our beloved Wave Dancer . We were now committed. We than had all the foam for the hull cores, barrels of resin, and huge rolls of matting and roving needed for the fiberglass skins delivered to our “domed stadium”. We kicked ourselves many times that we didn’t take a picture of this raw material stacked in one corner of the empty shed, so we could later show “before” and “after” photos. It was time to build the hulls.

Over the next several months we proceed to join the hulls with the beams I had built in the garage, and then to install the cuddy cabin, cockpit, and decks. By the spring of 1998, it was staring to look like a catamaran. Through the spring and summer of 1998, we continued with the major structural components: mini-keels, hatches, stairs, and interior. Then we went on to the very laborious work of fairing the boat before painting. Don’t under estimate that job!

By October 1998 we were ready to prime the boat and start painting. I really thought this would go quickly. I forgot that I would have to do two more complete sandings to sand off and finish the two layers of primer application. In addition we had to fill countless pinholes – a laborious process somewhat like hiking up a mountain – each time you get to what you think is the top, you see another summit!

The boat seemed to get bigger and bigger. Believe me, there is a lot of surface area on a catamaran. I clearly remember that last sanding: I had reached the end of my physical and mental endurance – I was exhausted. I was ready to move on to the next phase – any phase but more sanding!

We now started spray-painting the hulls bright yellow. It was around this time we decided on our boat name of Light Wave . The painting took over a month: the hulls being the easy part, it was the topsides, the nonskid, and all the masking and prep that seemed to take forever. Happily, the worst of the dust was gone.

By March 1999 we were in the home stretch. The center bridge deck cabin was completed so we took a week off from our paid jobs and lived on the boat in the shed so we could work all day and not waste time commuting. March, April and May were frantic months as we finished all the final touches: engine installation, rudders, windows, deck fittings, electrical, plumbing, mast, and rigging. See our outfitting page (for more details on what we picked and why, and things we would do differently now.

Initially, our electronic systems were relatively basic but included GPS and autopilot see the following link for all our electronic outfitting choices and reasoning for more details.

It was May 22, 1999 and we decided that Saturday, June 5th would be “Launch Day” so we could send invitations to all of our friends. On the Friday night before Launch Day, we still had a number of final things to do, many of them outside. Unfortunately it was pouring rain. We were tired and very wet but the boat had to go into the water next day so we persevered on till everything was ready.

The moment of truth came as Light Wave was lowered into the water. While still in the slings of the Travelift, I jumped aboard to check for leaks. Of course there weren’t any! More food and laughs and tours of the boat for all attending. It was a great day.

Emotionally drained that night, we slept in Light Wave in the water for the first time. It was another week before we actually went out for our first trip as we had to sell the shed, setup sails, and install some final deck hardware.

To sum it up, building a catamaran was a great experience. We learned a lot. Carllie and I grew closer together through it all. We had a great time doing it. We had a beautiful catamaran to show for it. Now it was time for a catamaran adventure !

[email protected]

Category: Our Catamaran Build Kits

Recommended equipment.

Quality suppliers & manufacturers

The schionning team have a lot of contact with equipment suppliers and manufacturers, and hear feedback on certain brands or systems from our many customers. there are many schionnings cruising the world and testing products longevity and the customer service offered by the manufacturer., on this page we will list products and companies that we know to provide above average quality and service. it is always growing, and if your company provides equipment used on our designs and you would like to be included - please contact us., engines & drive systems.

Visit:  https://oceanvolt.com

Batteries, Power Management

LITHIUM POWER (VIC)

Back in 2013 I knew that my boat batteries were reaching the end of their lives, I had been researching LiFePO4 cells for a few years and decided that I should install them. Unfortunatly I was unable to find a local supplier. So Lithium Power was established.

Technical Information

The technical information page is a collection of documents (mostly in pdf format) on the materials and systems used in schionning catamarans. including data sheets, engineering information, strength comparisons of each core material and informative articles from jeff outling the design of certain system such as engine choices and main sheet systems., detailed engineering data for your research, we understand that getting your head around the process of building your own boat, or having one built, can take a little while. to gain a greater understanding of the materials used in our designs, the below data sheets have been supplied by atl composites, and contain all of the technical data you could need regarding the composites we use. in addition are articles or documents written by jeff about certain systems used on our designs and why., all technical information and data sheets on west system/duflex/durakore provided courtesy of atl composites. for more information please see the atl composites website here., documents library.

Information Sheet – CE CERTIFICATION PROCESS

• Mainsheet Systems for Catamarans
• Motor Choices for Schionning Designs
• Weight and Weight Distribution Schionning Designs
• Schionning Designs Sailing Performance and Tips
• Hull Shapes and Performance – Power Designs
• Outboard Engines VS Diesels – Written by Ross McCombe
• An Outboard Installation That Works – Ross McCombe Follow up
• Data Sheet – DUFLEX BALSA for Catamaran Kit Builds
• Data Sheet – DUFLEX FOAM
• Data Sheet – FEATHERLIGHT Paper Honeycomb
• Data Sheet – WEST SYSTEM R105
• Data Sheet – PUMP SYSTEMS
• Data Sheet – MICROFIBRE BLEND 403
• Data Sheet – MICROLIGHT 410
• Data Sheet – MICROSPHERES 411
• Information Sheet – USING FILLERS
• Data Sheet – KINETIX RESIN Thixotropic
• Information Sheet – DURAKORE PLANKS 413
• Data Sheet – DURAKORE PLANKING 414

Kit Materials Contents

Kit materials' contents, so if you order a schionning kit, what exactly is going to arrive see an overview of the materials you will receive, and what each is used for during the build process. fibreglass cloth or tapes microspheres, microballoons or microfibers take a closer look and you can answer these questions., our schionning kits are a no nonsense, common-sense approach to building a boat. we offer great service, fast delivery and access to anything you could need for your boat straight from the supplier to your door. our construction plans and kits are sold with 100% professional boatbuilder support via phone and email, any time you're unsure or just need a second opinion, we're here..

Our kits contain all of your basic materials to build your boat to a faired shell stage, ready for painting and fit-out. We have sail-away costing estimates available for all of our standard designs, and this will give you an accurate idea of the overall cost of your project. This costing varies depending on your level of finish, as you can imagine different options vary greatly in price.

Below is a quick glance at what your Schionning Kit will include and what each item is primarily used for, we hope this is helpful and if you should require more detailed information please don’t hesitate to contact our office.

What do I actually receive?

DUFLEX PRE-LAMINATED PANELS

DuFlex pre-laminated panels are the main and most important material used in our kits, predominantly in the flat panel designs, however they are used in Strip-planked designs also, though to a lesser extent. These panels are 2400mm x 1200mm and are CNC routed to speed up build time on our Wildernes X Series, as well as some of our power designs. For internal furniture, a paper honeycomb core is used instead of the end-grain balsa wood core that is used for main structural areas. The use of this is purely to save weight in the shell and therefore produce a faster, more responsive catamaran.

KINETIX LAMINATING RESIN & HARDENER

WEST SYSTEM EPOXY RESINS

FIBREGLASS TAPES (DOUBLE BIAS)

CARBON FIBRE CLOTH

FIBREGLASS CLOTH

The kit process, building your own boat can be a daunting prospect, however to demonstrate each step in the kit assembly process, we've created this guide for you to study. as you can see our kits are the ultimate in building efficiency and have been streamlined over 30+ years to ensure that you're on the water faster and with less effort., how does it all go together.

The first step to building your dream catamaran begins with a strongback – this is a square frame used to position the temporary frames that will be used to form the hull shape. This frame will be set up and must be square and accurate, a string or laser level can be used to achieve this.

The forebeam is now installed along with the striker attachment fitting, as shown above. The bridgedeck is installed shortly after and taped onto the bulkheads with webs installed, this now completes what is a quite stiff and strong platform to work on.

Now that the bridgedeck is in place, the forward webs and dash will be fitted. At this stage, all furniture and internal work begins, with the main panels left off for ease of access when working.

Material Choices

Schionning material choices, solutions that work best for catamarans & why, our designs are based on cored composite construction techniques using west system epoxy resin and knitted fabrics. but given the range of today's composite technologies, which solution works best for catamarans and why written by jeff schionning, selecting the correct materials, resin choices.

It also fully protects the boat against water absorption and it can not develop the dreaded Osmosis.

We choose ATL Composite’s resin systems for their superior quality, reliability and value for money.

Having worked closely with the ATL Composites team and their products for many years, we know we can stand by their material solutions, and rely on great service should something unexpected happen.

This may not seem important but when working with a material for an extended period of time, the small things make all the difference.

CORES Which One to Use?

• End-Grain Balsa – 150kg per cubic metre
• Superlight Balsa – 94kg per cubic metre
• Western Red Cedar – 360-380kg per cubic metre
• Foam – 80kg per cubic metre

BALSA END GRAIN (150 kg/cubic metre)

Balsa  has very good values and we can produce a shell using a very light laminate. It will be very stiff and very resilient to fatigue.

It has exceptional qualities including very high compression strength, extremely good sheer capabilities and fantastic sheer stiffness.

Compressive strength is the resistance to collapsing when pressure is applied perpendicular to the surface as when pushing directly onto the material with the point of your finger. Balsa is far stronger than Foam (80kg/cubic metre) in compression.

Balsa is also very strong in shear. This is when the core sample is held flat between your hands, one hand slid one way and the other slid the opposite way, when the core tears through the middle the core has failed in sheer. The amount of stretch you feel before the core shears is shear stiffness. To compensate for sheer weakness the core is made thicker. So 13mm Balsa may be equal in sheer to 19mm Foam.

(80 to 200 kg/m³)

There are many boats sailing that are built from foam as it’s mechanical properties are good for boat building.

• Initially one would expect this cat shell to be lighter as it is ½ the weight of Balsa. We do have to compensate for its weaknesses and will then add to the reinforcement the reinforcement on the outside to spread that compression load over more core and need a triaxial type weave to compensate for the veneer content that runs fore and aft on the Durakore.
• Secondly, we need to increase the Core thickness to compensate for the shear value, usually neutralizing the weight advantage.
• We only use structural foam core that is closed-cell and cross-linked.

The end result using foam core amounts to a very similar total boat weight. Professional builders can achieve a good result but usually use vacuum bagging and very good molds to achieve this.

Secondary Issues

Balsa can absorb water. It needs extreme neglect to rot (very unusual). Water soaks along the end grain quickly. It travels very slowly across the grain. We use balsa under the waterline especially because of it’s high compression strength for beaching etc. any core type must be sealed. Damage to all cores results in the same sort of repair. Notice a damp spot remaining when drying out to anti-foul… simply grind back the surface glass exposing the core, dry it out and re-glass – it’s that easy.

Timber cores are cheaper than Foam in most cases.

A light, high tech cat returns a far better (often 2 – 3 times) re-sale than lower tech materials. Often saving $10,000 on materials initially, loses $200,000 on re-sale – a serious reality.

Our boats can be built using Balsa, Foam or Western Red Cedar. Combine strength, stiffness, lightness and cost, with ease of use – it just makes good sense!

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Open Source 13-15m Catamaran Plans

Discussion in ' Projects & Proposals ' started by archie1492 , Jan 3, 2018 .

archie1492 Junior Member

Dear all, I want to create a detailed building information model for a 13 - 15 meter catamaran that is capable of being CNC cut and assembled. I need some help finding plans I can use as a basis of design. Specifically, I need the hull profile information. Section cuts through the hull will give me the ideal contours for a boat of this size. Can someone help? After weeks of searching, I still cannot find these online. For now, this is merely an exercise in my 3d modeling capability. I'd like to share my drawing work with the forum if I can get some assistance to start off. There are future possibilities I am also considering. I'm an experienced Architect & construction designer with a strong background in computer aided design. Once I've modeled the boat in 3d, I would like to flatten the various parts and create plans for the individual boat parts to be CNC cut. I would like to build a small scale model first (1:2o or perhaps 1:10) with the ultimate goal of building the boat full scale.  

TANSL Senior Member

This is a very simple catamaran which, if you are interested, I can give you a lot of information. It is not a spectacular boat but it can help you in your first steps with boats. LOA = 16 m, Lbp = 14.6 m  

Thanks I really appreciate it. The hull lines for the motor cat you've provided are not quite what i'm looking for. I'm specifically looking for the hull lines for a 14m catamaran sail boat. I guess there is some standard for these contours especially the area below the waterline. Check the attached document as well if anyone is interested in this.  

Attached Files:

catdimension.pdf

I'm sorry, you never specified that it was a sailing catamaran. I thought that to carry out your purposes, " For now, this is merely an exercise in my 3d modeling capability ", any model was valid. Apparently, you have different purposes than, in addition to, to practice with 3D models. The better you clarify what you are really looking for, the better someone can help you.  

Hi all, Here's an example of what kind of information I need to get started. Optimising Hull Lines for Performance https://www.graingerdesigns.net/the-lab/optimising-hull-lines-for-performance/ The boat shown here is a 8.5m cat sailboat. I'm looking for something a bit larger in the 14m range. Also, the images only show one of the hull profiles. I'd like profile lines for the entire boat. I will post some other images I've found online showing profile lines for smaller boats. I still cannot find any 14m hull lines. Can anyone help?  

grainger_1488019480.jpg

Grainger_1488019410.jpg, grainger_1488019333.jpg, grainger_1488019265.jpg, grainger_1488019219.jpg.

Here are some other hull lines I've found online. Hope this is useful to anyone else looking for this information. Thanks!  

Evergreen Lines small.jpg

Hull-lines.jpg, shark-20.jpg.

You could take any of those boats and scaleb the lines to get the desired length. Since it is only a 3D modeling exercise, you do not have to worry about anything else. You could even make a mix of 2 or 3 of those models to get the one you are looking for.  

Thanks Tansl, I'd like to make the boat drawings accurate for the 14m size. Perhaps one day I will develop this into something worth building full scale. The more accurate I can draw the boat, the more I will learn about the boat design.  

Maybe it does not look like it but I would like to help you. If you do not find what you want on the Internet I could draw a lines plan, strictly following your instructions, which would help you to make the 3D model. Or, if you find something similar on the internet I can adapt it to your needs and fill in the information that you indicate you need for your work. I insist that starting from the shapes of a 10 m boat you can get the shapes of a boat of 14 m, with total accuracy.  

Dolfiman Senior Member

archie1492 said: ↑ I'd like to make the boat drawings accurate for the 14m size. Perhaps one day I will develop this into something worth building full scale. The more accurate I can draw the boat, the more I will learn about the boat design. Click to expand...

Cata 14m with Gene-Hull UE Catamaran 2.3_2018 01 15.ods

Gene-Hull Catamaran 2.3 User Guide_2018 01 16.pdf

Hull for cata 14m with Gene-Hull UE Catamaran 2.3_2018 01 16.pdf

Dolfiman, thanks so much! This is exactly what I was looking for. It's very interesting and probably a bit over my head at this point. I think this should work for modeling the basic hull shape. For the bridge deck and all of the stuff above the hull I can model this with a bit more creativity. Although, I'd like to learn more about understanding the center of gravity for the boat and the proper location of the mast. Are there any rules of thumb about this? Thanks again!  

archie1492 said: ↑ I think this should work for modeling the basic hull shape. Click to expand...

Cata 14m V2 with Gene-Hull UE Catamaran 2.3_2018 01 15.ods

In complement to illustrate this first approach, my good friend Alain did some 3D views here attached of the hull V2 version with Multisurf (using fit for purpose ouput data in section 5. of the above file). To inspire you , some other examples of cata, more sport/day sailer oriented than the Saona 47 : - R/P 45 (Reichel-Pugh) : multihull http://reichel-pugh.com/tag/multihull/ - Dazcat 1295 : in this video, from 1:45 the launch, you can see the hulls from various angles https://www.youtube.com/watch?v=0BZF4Udda5E - SIG 45 (VPLP design) : from 1:20 you can see the winward hull fully lifted ​  

dean 1962 New Member

archie1492 said: ↑ Dear all, I want to create a detailed building information model for a 13 - 15 meter catamaran that is capable of being CNC cut and assembled. I need some help finding plans I can use as a basis of design. Specifically, I need the hull profile information. Section cuts through the hull will give me the ideal contours for a boat of this size. Can someone help? After weeks of searching, I still cannot find these online. For now, this is merely an exercise in my 3d modeling capability. I'd like to share my drawing work with the forum if I can get some assistance to start off. There are future possibilities I am also considering. I'm an experienced Architect & construction designer with a strong background in computer aided design. Once I've modeled the boat in 3d, I would like to flatten the various parts and create plans for the individual boat parts to be CNC cut. I would like to build a small scale model first (1:2o or perhaps 1:10) with the ultimate goal of building the boat full scale. Click to expand...

• Advertisement:

Archie, I have been looking to do the same thing. Where are you at on the project? Very interested in hearing all about it. Thanks.  

The Open Trawler Project!

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• Boatbuilding Links & Resources
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Plans and Kits for Catamarans and Proas and other Multihulls

Check out my page on Advantages and disadvantages of multihulls

If you're planning a boatbuilding project you might like to check my boatbuilding resources. These are articles from my website and some outside links and build diaries.

Multihull plans in no particular order

Email me if a link is broken or if I've missed a boat. I try to keep my links good but things change quickly on the web.

I try to include most plans that I run across. I only exclude the ones that seem to be dubious, some are plagiarized or some just seem to be of terrible quality, or a website that includes pop-ups or other nasty things, that I don't dare include them. I have not personally checked all plans. Before building, do your homework.

• Bruce Roberts has aluminium and fiberglass boat plans for large Catamarans
• Schionning Designs has plans and kits for Cats, Trimarans and a keelboat.
• From Wooden Boat Magazine plans for a 20 ft Trimaran. Also a Sailing Outrigger Canoe
• Kurt Hughes has both large and small Catamarans and Trimaran plans.
• Sailing Catamarans has beach cats.
• Woods Designs has small and large boat plans
• K-Designs has Little Tri sailing trimeran dinghy and others.
• Dudley Dix Yacht Design has a large cruising catamaran
• Svenson's Free Boat PLans has an old Mechanix Illustrated Hobby Kat plans along with many other boat plans
• Duckworks Magazine has a whole section of small sailing multihulls.
• James Wharram Designs offers plans and will build also.
• Tornado Building Plans free from The Beachcats.com
• Hartley Boats has a few designs for sailing cats.
• Applegate Boatworks has plans for Blue Joseph, a proa
• Glen L Offers plans for La Chatte, sailing Cat.
• Scarab Folding Trimaran Dinghy.
• Selway Fisher has a design for simple Catamarans.
• Slider Cat Ray Aldridge design from Duckworks
• Gary Dierking is well known in the Proa community.
• Chesapeake Light Craft has many designs, well thought out plans and kits. This is Junior outrigger.
• Also from CLC 2 large proas Madness, and Mbuli
• Novacat 17 Plans and build photo IN German, get mr. Google to translate.
• From Svenson's popular mechanix plans Cats Paw free plans
• Fyne Boat Kits has several multihull designs. He also offers add-on outrigger for canoes and kayaks.
• Instructable for a Polytarp Crab Claw sail for a proa
• A one day proa project Maybe not quite perfect but worth looking at. Here's another instructable sailing outrigger canoe
• Angus Rowboats has a sailing conversion plan with outriggers.

Too Much Choice

There are a great number of large cruising catamaran and other multihull plans out there. I think one of the reason is that building a large catamaran is easier than building a cruising size keelboat. Many designers feel confident that the home builder has a good chance of success in putting together quite a competent multihull.

I have not included all the large multihull plans and kits I have found, nor have I included many of the home made single effort catamarans that are out there.

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I try to be accurate and check my information, but mistakes happen. ALSO keep in mind that not all boat plans are well designed. Old Banks Dories are particularly tricky because they were notoriously unsteady until they had some weight in them. Check the boat forums, many people have built dories. I have not built these boats and I can't recommend or proscribe any.

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building a catamaran

A collection of sailing catamaran building logs, from sailboat plans to yacht launch. This 11.6m 'EASY Series' catamaran, joining other catamarans to lat and longs unknown...join us on our journey

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Plywood and Epoxy Catamaran

This 'glass-over-ply' sailboat is proof that a DIY'er can successfully build an ocean-going multihull. Plywood construction is the cheapest building method available and very forgiving while one hones their skills. Finishing with a solid fiberglass outer is also a task made easier, given the amount of glassing and gluing needed during such a project.

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Many sailboat plans to choose from.

Is it cheaper to build or buy.

There are many yacht plans to choose from, but dont kid yourself. Many have tried to do it on the cheap and their result shows.

If there was a cheaper way, the sailboat designers would tell you. Afterall, they would use that reason to sell there plans!

If you want a yacht with all 'bells and whistles', keep working because it does cost money.

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Catamaran Construction – Hulls, Laminates, and Composites

• Post author By BJ Porter
• Post date October 15, 2020
• 3 Comments on Catamaran Construction – Hulls, Laminates, and Composites

It’s a given that catamarans are more sensitive to weight and loading than monohulls. Catamaran builders strive to build the lightest boats they can without sacrificing strength and stiffness, and have adapted new building techniques and materials to meet this target. Cutting weight allows more passengers and gear without sacrificing performance.

And the marketing materials reflect it–they load every review and website with polysyllabic technical jargon describing the design and production choices each builder made to deliver the best boat they can.

But when you’re reading a brochure and you come across phrases like “ hand laid bidirectional GRP ” or “ vacuumed bagged e-glass with vinylester resin over a Divinycell core ” do you know what that really means?

All modern production catamarans are made with “FRP” construction (for Fiber Reinforced Polymer). Composites aren’t new–it’s just using materials together to strengthen the whole assembly. Straw was added to bricks centuries ago, and steel reinforced concrete is a staple of construction over the last century. For boats, it’s the use of stranded fibers and cured resins which make FRP different.

The term “FRP” doesn’t get into the technical detail of which fibers and which plastics, and how they’re put together to build your hull. There’s a wide variety of fiber types which can be stranded, woven, chopped or sprayed in a varied of patterns then combined with several types of resins to make hulls with different characteristics.

Some FRP techniques produce lighter, stronger shapes, while others are quicker to build and less expensive to produce. The choice of technique is a function of many factors, from the number of hulls and parts to be built, the type of parts, the budget for the project, and many design specific requirements for weight and strength.

1. FRP Basics

The principle behind all FRP construction is the same – you lay our fibers in the shape you need, then saturate them with resin, removing all the air and voids you can. Resin is left to cure, then the piece is ready to finish and use.

The reality is more complex, since building a boat isn’t like making a flat board or a simple door. You’ve got a complex shape with a designed set of curves to build. “Tooling” is the set of shapes to make the boat parts; molds to cover with fiberglass to get the right shapes.

That’s what makes FRP so effective – you can make almost anything out of it. But to do so requires a lot of choices about what you need for the project at hand.

There isn’t a “best” all around material or technique choice for all jobs, and sometimes a lower cost technique or easier to work with material may be the better solution to the problem.

A. Fiber types

Fiber choices in the last few decades have expanded past the glass fibers used in the first mass produced boats in the 1960s. FRP construction wasn’t new even then, they built the first composite boats using modern fiberglass in the 1940s.

The major fibers used in marine construction fall into three categories – glass, aramids, and carbon. The primary differences are in the strength to weight ratios of the fibers, durability, elasticity, and cost. Some construction may use blends of fiber types to combine performance characteristics.

Glass – the most common material still, because of its low cost and versatility. The most common variety used in GRP (Glass Reinforced Polymer) is “E-glass” which refers to its strand size and mineral content. Other grades have different and sometimes better mechanical properties, but may be more expensive and less appropriate for boat building use. Fiber sizes run 10 to 25 microns for E-glass, though other grades may be smaller.

Brands like Leopard, Lagoon, and most higher production volume builders use E-glass.

Aramids – this includes brand names like Kevlar, Technora and Twaron. They have higher tensile strength than E-glass, and resistant abrasion and punctures. Kevlar is a common choice for bullet proof body armor, and can built a tough, lightweight hull. The materials can be difficult to work with, as it is very tough to cut the cloth. It is often blended with carbon fiber or other materials – Catana is known for using Twaron blends in hull construction.

Carbon – the ultimate in lightweight, strong construction material. Carbon fiber is the most expensive fiber, and is available in a variety of weights, grades and strengths. Fibers are smaller than glass – down to 5 Micron.

The lightest, most expensive hulls are made from carbon, but a catamaran builder may use carbon in places other than the hull to add strength and stiffness. Carbon boards, rudders, and reinforcing structures can enhance performance without driving the price of the boat beyond reach. Carbon is the fiber of choice for many custom builds, racing cats, and Gunboat.

B. Mats, Strands, Roving, Direction, and Weights

Fibers are woven into matting and cloth for construction. Depending on the application, different weights of cloth and cloth patterns and weaves may be more appropriate for the job.

Cloth weight refers to the weight per square yard (or meter) of the cloth. A square yard of nine ounce cloth weighs nine ounces. The heavier the cloth, the stronger it is in a laminate.

Fibers carry loads along their length, so cloth weaves have directionality to their strength. Most builders use several layers of cloth with different orientations to give good universal strength to hulls. Specific FRP applications with strict load-path requirements may have more unidirectional fiber layering – for example, a chainplate manufactured from carbon fiber may use unidirectional fiber.

Cloth – fiberglass cloth is commonly used on outer layers of composites. Cloth may have unidirectional or bidirectional strength. Bidirectional cloths have maximum load strengths in two perpendicular directions. Variations on weaves like a modified twill allow a more flexible cloth for better shaping around complex molds.

Mat – is omnidirectional strands of fiber compressed into a cloth. This is often held together with a resin soluble glue, which makes mat great at conforming to mold shapes without folding and bunching as it collapses when wetted. Because the strands do not align, fiber strength is the same in all directions.

Woven Roving – a heavier cloth made from larger bundles of strands. Woven roving allows for quicker buildup of material and strand weight.

Most FRP layups include multiple layers of different cloth and mat. Finished layers may be finer cloth over courser cloth, over woven roving and mat.

Three primary resins are in common use in marine construction – polyester , vinylester , and epoxy . All resins have materials safety concerns and require care in their use and handling.

Polyester is the least expensive and requires breathing protection because of the VOC emission (Volatile Organic Compounds…nasty, smelly fumes). It doesn’t have good bonding/gluing capability, and should only be used with glass fibers for structural building. Some polyester resins are referred to as “isophthalic” resins.

Vinylester is chemically similar to a hybrid of polyester and epoxy, and performs best with fiberglass. It shouldn’t be used in high strength applications with carbon or aramid fibers. It has some adhesive qualities which polyester lacks, it shrinks less during curing, and has better impact resistance.

The added strength of vinylester coupled with increased water resistance makes it an attractive option for many catamaran builders. It costs less than epoxy, but still has better performance than polyester.

Epoxy is the most expensive, but is three times the strength of the others. It offers the best adhesion and the only resin for building structural elements with carbon and aramid. It resists water intrusion better than the other resins, resists blisters, emits no VOCs, and shrinks less. The major drawback is it is more brittle if it takes an impact.

While epoxy is “the best” in terms of strength and ease of building, there are many applications where other resins are appropriate. Budget is a big driver – a boat made from E-Glass doesn’t need epoxy resin, and considerable cost savings to meet a construction price target may drive the choice.

They can build quality boats from all material combinations, but price and performance will drive materials choices to keep some boats more affordable.

2. Cored Construction

What’s the best way to make fiberglass strong? To a point, you can make it thicker. As it gets thicker, it gets heavier. A hollow shape can take more compressive load than a solid one of the same weight, and the same principle applies to fiberglass construction.

Consider an I-Beam used in building construction. It has the same strength (or more) as a solid rectangular beam of similar mass. The compressive load on the beam is supported by the outside edges of the material, the metal in the middle doesn’t contribute much to the strength. So we can remove metal to get the “I” shape while still keeping those sides rigid, making a lighter girder with less material.

The same principle applies to cored construction with fiberglass. Making a sandwich of two layers of fiberglass with a light core between them allows for the greater strength with weight savings.

There are drawbacks – the biggest risk is damage which breaks the skin, which can let water into the core. Earlier cored construction used materials prone to saturation and rot if they got wet. Some builders opt to do cored construction above the waterline and solid below to minimize some of these risks.

But the advantages in weight savings and increased stiffness offset the drawbacks, and there may be a few other side effects like sound and temperature insulation. Like resins and fibers, core materials offer distinct advantages, disadvantages and price points.

Most builders have adopted a hybrid approach, building solid hulls below the waterline, and cored hulls and decks above. This gives a balance of weight and safety.

A. Balsa Core

Balsa is light and inexpensive. The first cored construction used balsa, but it has the disadvantage of being wood. As a natural material, if it gets wet it can rot and break down. Builders use “end grain” balsa – shorter cross cut sections – to prevent wicking of water if there is an intrusion.

B. Foam Core

Closed cell foam cores give good strength to weight savings while minimizing water intrusion. If you get water in the core, it won’t spread very far. Divinycell is a popular PVC foam core, though there are several choices with different densities and compressive strengths.

Some foam cores are not suitable for heat treatment, but infused or vacuum bagged boats like the Outremer and PDQ do well with it.

C. Honeycomb

Honeycomb cores are often the most expensive, but also give some of the best strength to weight ratios. Honeycombed cells made from resin cured aramid papers are some of the best, but also among the most costly. They offer good stiffness, but can be hard to shape. Aluminum and other resin-infused papers are other core materials builders can choose from.

3. Construction and Resin

When building a hull, there are optimal ratios of fiber to resin saturation for target strength and weight. Too little resin and you may not have enough strength (or worse, voids and gaps), and too much, and you’re just adding weight without adding strength. Resins are also a significant material cost in building the boat, so over application not only increases weight but adds cost.

There are many ways to assemble the cores, fibers and resins to build a finished laminate hull – we’re addressing the most common in boat building. Each approach has strengths and limitations, and an impact on the bottom-line cost to build the boat. Any voids or air pockets in the laminate can be disastrous; these techniques have been developed to increase saturation and reduce the risk of voids.

A. Hand Layup / Open Molding

As the name implies, this is the application of resin by hand to cloth as it’s laid into a mold. Wetting is done with a brush, and the laminate is rolled out to remove any air pockets and voids. This is the simplest way to lay up fiberglass, but also the least precise and consistent and will use the most resin.

Skilled craftsmen have built some of the finest vessels in the world this way. Though it’s more popular with monohulls, which are less sensitive to weight, many catamarans built with hand layups on open molds are still out cruising and performing well.

B. Spraying

Using chopped-strand fiber mixed with resin, a “chopper gun” can spray the mixture into a mold to lay down the composite. A consistent thickness can be difficult, but this is a low cost construction technique which makes a very resin-rich laminate. Using sprayed fibers gives lower strength in all directions compared to meticulously laid down mat and bi-directional cloth. But it is a quick technique popular with mass produced, smaller boats.

It is an excellent technique for parts with complex geometry where weight is not an issue, but you will not see it often in catamaran construction. It’s heavy with resin without any resultant increase in strength.

C. Vacuum Bagging (Wet layup)

When an open molded component has been laid up and wetted with resin, vacuum bagging takes the process a step further. After the wetting is complete, air tight plastic bagging is secured around the wetted area, and the air is pumped out of the bag. The vacuum pulls excess resin out and collapses air pockets.

The goal is to get thorough wetting and produce as strong a laminate as possible without excess resin. Knysa and Leopard are two builders that use vacuum bagging on their hulls to reduce weight.

D. Resin Infusion

For resin infusion the cloth, matting and core is laid in place dry, then sealed in an air-tight bag. A vacuum pump attaches to one side of the bag, and on the other a feed for resin. The vacuum sucks the air out of the dry cloth stack, then pulls the resin through the stack, infusing and wetting it.

Resin infusion, when done right, gives the lightest, strongest laminates with no voids and the minimum resin weight for maximum strength. SCRIMP is a variant of the resin infusion process used by some builders, including TPI which build many early Lagoon cats.

E. Pre-preg

Using pre-preg (for “Pre Impregnated”) cloth for your laminating gets rid of the resin bucket. They manufacture cloth with a partially catalyzed resin pressed into it, then it’s chilled or frozen to stop the curing process. There is no need for seperately mixed resins, and there’s no worry your resin might “go off” and harden before you’re done wetting the cloth. Instead, the cloth is assembled, vacuumed, then heated to kick off the curing process.

There are both advantages and disadvantages to using pre-preg for your laminate work. The big disadvantage is the cost; it is most expensive material to use. You also need to chill and store the cloth until you need it, though some can be at room temperature for a couple of weeks without kicking off. And you need an oven which requires some clever tricks if you’re building a forty or fifty foot boat.

But the strength to weight ratio will always be perfect. High tech honeycomb cores are best suited to pre-preg lamination, and without racing against resin cure times, you can ensure perfect cloth placement and precise layout in the build process.

The primary use for pre-preg in boating is high performance race boats. With catamarans, pre-preg may be used high load parts, like Gunboat does for foils and rudders.

4. Industry Examples

Across the catamaran building industry you’ll find almost all the above techniques and materials used, though some are less common. You aren’t likely to find chopped strand sprayed layups in ocean going cats, and hand layups can lead to heavier hulls than weight sensitive catamaran designers prefer. Most manufacturers have moved to vacuum bagging or resin infusion, with a few of the highest end boats using pre-preg for key components.

Built by Robertson & Caine in South Africa, the hull material is vacuum bagged, end-grain balsa-cored E-glass with polyester.

Hand laid, bagged vinylester over an Airex foam core in the hulls.

Earlier Prout catamarans like the Snowgoose 34 featured hand laid solid FRP hulls and decks. Over time they switched to foam or balsa cores for decks and above the waterline.

Older PDQ boats were made from vacuum bagged vinylester – solid below the waterline and cored with CoreCell foam above the waterline and in decks. Newer PDQ models switched to epoxy resin.

All glass is vacuum bagged. Below the waterline is solid E-glass and vinylester. The rest is unidirectional, bidirectional, and triaxial cloths over a Nida-Core polypropylene honeycomb core with isophthalic and vinylester resins.

The Gemini cats are built with a solid hand layup of woven roving and fiberglass mat and polyester resin. Decks are cored with end grain balsa. The Gemini 3200 introduced vinylester resin into the layup to prevent blistering.

Older Lagoons were SCRIMP infused vinylester with and end grain balsa core above the waterline and in the decks.

Newer Lagoon catamarans use polyester and vinylester resins, also infused with balsa cores above the waterline and solid below.

With a carbon fiber inner skin, Catana also uses Twaron aramid fibers in the sandwiched hull over a foam core.

Fontaine Pajot

Primary hull construction is resin-infused vinylester with a balsa cored hull and deck.

Beneath the waterline, Outremer uses a single layer, solid vinylester laminate for safety. The hulls and deck are vinylester with a Divinycell foam core. They stiffen certain components with carbon for rigidity and durability.

Gunboat hulls are epoxy infused carbon fiber with a Nomex honeycomb core. They build dagger boards and other high load components with pre-preg carbon.

• Tags Buying Advice

By BJ Porter

Owner of Hallberg Rassy 53; world explorer.

3 replies on “Catamaran Construction – Hulls, Laminates, and Composites”

Excelent. Thank you for this I learned allot. Johan

Very straight forward information. Thankyou for doing this.

Damn…What an Amazingly Informative Article. *Cheers*

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Projects: Constructing a 40ft catamaran with WEST SYSTEM epoxy

Work doesn’t necessarily slow down after retirement, as engineer Martin Ellison proved when he left his teaching post at the age of 59 and set about building his first boat. What started as some prompting from his wife to find a meaningful project evolved into the idea of building a 40ft catamaran. Martin tells epoxycraft how it all came about.

I have always loved being on or near the water and wanted to have a boat of my own. As someone who has renovated a few houses in the past, I wasn’t daunted by the idea of building a wooden boat from a set of plans, although I’m not sure it was the scale of project my wife had in mind!

I chose to build a catamaran because I wanted the space and stability; preferring a power cat, I searched online for some designs and went for the Skoota 36 ( Woods Designs ). This is a relatively simple timber and plywood design sheathed in fibreglass, although I have slightly modified the design to increase the length to 40ft so that I could enlarge the accommodation space in the hulls.

When I began in earnest in September 2014 I didn’t even have a boat shed, so that was the first project. It was ready for action by March 2015 and I have been steadily working on the boat for the past nine months.

I’ve used WEST SYSTEM  epoxy all over… and found its strength and versatility to be ideal.

For the build I’ve used WEST SYSTEM® epoxy all over – jointing, filleting, waterproofing and sheathing and have found its strength and versatility to be ideal for this project.

I’ve mainly used WEST SYSTEM 105 Epoxy Resin® with WEST SYSTEM 205 Fast Hardener® . In addition, I’ve combined the epoxy mix with WEST SYSTEM 403 Microfibres and WEST SYSTEM 409 Microsphere Blend® to ensure all the gaps have been thoroughly filled. When it came to sheathing, I used 300g and 600g Episize™ Biaxial Fabric and 300g woven WEST SYSTEM 787 Aramid Fabric® to provide extra protection below the waterline.

The boat build so far has taken just over 1100 hours. It’s a big boat and there’s a lot of work – mainly woodwork – involved in completing each stage. I’m enjoying it though, it’s very rewarding and most of the build has gone pretty smoothly.

As luck would have it there is another Skoota 36 being built in Canada which is about one year ahead of me and the owner has very kindly shared his build photos, which has been a great help. People say it looks very difficult but in practice it isn’t – it’s simply a case of following the plans and having the confidence to get on with it.

There’s still a bit of a way to go but I’m really looking forward to turning over so we can finalise the internal layout and then getting her in the water and cruising in her.

Our thanks to Martin Ellison for sharing his story. We wish him well and will be following him closely as he completes his build.

If you would like more information about this project you can follow the build on https://my-new-cat.weebly.com

Back to projects

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Lochaber Coastal Rowing Club and the St Ayles Skiff Project

Life Aboard Speranza

• BUILDING RAKU FROM A KIT
• Duflex Kit Construction in 9 Steps

BUILD YOUR RAKU CAT WITH A DuFLEX KIT BY FOLLOWING THESE NINE BASIC STEPS

Step 1. Kit Design

Work with us to finalise the details of the design you have chosen including any design options or additional modules to be included in the kit.

We will determine the laminates, the number of panels required for each laminate, create the cutting files and prepare a quote for the kit if it is not already priced.

Once the design details and pricing are confirmed you are ready to place your order.

Step 2. Unpacking

2. The kit arrives at your workshop door, usually by container, as a stack of 1.2m x 2.4m routed composite panels ready to be joined. The shipment will normally include additional reinforcements, resins, and ancilary products as specified.

Unpack the shipment and stack the panels out of the way of the space where the panels will be joined.

If you have purchased a joined kit many of the panels will already be joined up to the length that can be shipped in a container (12m).

Step 3 Joining the Panels

Set up the work space where the panels are to be joined.

The panels have a scarf join called a Z join that facilitate the join without needing tapes.

The joining can be done with a heated Z press that cures the epoxy join quickly. Alternatively they can be joined with clamping pressure.

If the panel are are being joined with the Z press you will need an elevated work bench the full length of the longest panels you are using. (image below).

If you are joining them with a clamping technique the space can be on the factory floor.

A nesting booklet is provided with the kit to show how the panels are joined (right)

Joining the panels with  clamping pressure

Panels are being joined into a single long panel by painting the surfaces of the scarf join with epoxy screwing through plywood battens that have a release film applied to one side.

Joining the panels with the Z Press

Step 4 Stacking Joined Panels

Once the joins are cured the panels are stacked to one side until they are needed for the job. The inividual parts should not be cut free of the panels until they are required.

Bulkhead and floor panels will be needed before the hull sides and cabin top so they should be left to the front of the stack wherever possible.

Step 5. Separating the Parts

When assembly is ready to begin the individual parts are separated from the panels by cutting the joining tabs. It is likely you will be building onto moulded hull bottoms that have been built from strip planking or another method of building moulded components. The process for building moulded components is described in another article.

Step 6. ASSEMBLY

As the joined panels are assembled onto the job you will need to apply glass tapes to the joins as specified in your plans.

Panels can be surfaced and coated inside and out with high build while they are on the workshop floor to minimise fairing time once they are assembled to the boat. The paint on the panels shown here has been kept back from the edges to provide a good bond for the tapes.

Smaller items such as steps, seats and dagger cases are nested into the kit and for the more complex parts diagrams are provided to assist with the assembly process.

Step 7. Interior

Interior kits can be ordered with the primary kit, or they can be ordered later when final decisions have been made about the interior arrangement.

A compromise solution is to order the interior as a set of plain planels that can be cut to shape on site after finalising the layout.

Step 8 Fairing, Painting, Hardware Installation

8. The DuFLEX construction process goes a long way to minising the amount of fairing that has to be done, but inevitably any boat that has not come out of a female mould will require some level of fairing and surface preparation prior to painting. 

The fillers and resin systems required for the fairing work are normally supplied as part of the kit.

Hardware installation is the same as for any other form of construction using high density core inserts or consolidated laminate in way of fittings.

Step 9. Sailing

Go Sailing. This Barefoot 40 Catamaran was built entirely with a Duflex kit in Foam/Glass and Epoxy resin systems from ATL Composites

DuFLEX Kits are manufactured and supplied world wide by ATL Composites

atlcomposites.com.au

And in Europe by VDL Composites

www.vonderlinden.de/her/28/vdL-Composites-GmbH

For more information on DuFLEX and associated Products 

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Catamaran & Small Boat Building

to my website. Here you’ll find photos, stories and information on building boats large and small, with tips and tricks I’ve picked up along the way. I built this website originally to accompany my YouTube channel . The blog section has information on various topics.

A 12m cruiser/racer catamaran – 2 yrs & 9 mths to build – launched 15th August 1997. Details of the build.

Small boats

Small boats you can build in your garage.  A good family project and a way to get a taste of boat building. See how they were built.

Plans to build your own boat. Packed with information for the first time builder. Start building your boat now.

Where to start

Building your own boat and sailing off over the horizon, is a dream that lives inside many. Well at least that’s the impression I get from the many people I met while building Tokyo Express (TE) and the feedback now f rom the videos on YouTube.  After years of dreaming, at 39 years of age I finally turned that dream into reality with the launching of Tokyo Express. This website is about my journey.

You don’t need expensive kits

or exotic materials to build a boat. You don’t need expensive tools or a degree in engineering either. I fabricated most of the parts and systems on Tokyo Express (TE) from scratch. Steering system, steering wheel, doors, hatches, fore beam, catwalk, daggerboard, rudders, engine mounting, generator, electrical system and plumbing.

Even the mast I bought as a kit. I had more time than money so I built everything I could. There were no exotic materials used and yet I ended up with a robust, lightweight and extremely competitive boat that was lighter than a typical production boat.

If I hadn’t been designing and redesigning many parts of the boat, learning for the first time how to do things and building a shed, the boat would have been finished a lot quicker.

On the Tokyo Express page

page you will find an overview of the steps I took building TE. If you are thinking of starting a similar project, this is a good place to start. It was a lot of work, but it was also the most rewarding project I have undertaken. It was well worth the sweat and tears. Please look around. Email me if you have questions…

Recent Posts

• Catamaran vs Monohull

by Tim Weston | Mar 11, 2019 | Building , Cruising

Catamaran vs Monohull If you are thinking of building or buying a yacht, you have a significant choice to make, before you even start looking at individual boats. Do you want one hull or two? Deciding between a catamaran and a monohull is a big decision and one worth...

• Going fast – in small boats – hull speed.

by Tim Weston | Sep 30, 2018 | Building , Plans

Going fast - in small boats (with a small motor) This article looks at how to go fast, in a boat with a small motor. Plodding along at snail’s pace can get a little boring. No matter how relaxed I am and how much time I have nothing puts a smile on my face quicker...

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