catamaran hull plan

DIY Cruising Catamaran: Complete Building Guide

As an Amazon Associate, we earn from qualifying purchases. We may also earn commissions if you purchase products from other retailers after clicking on a link from our site.

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!!

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Save my name and email in this browser for the next time I comment.

Recent Posts

Must-Have Boat Gear for Catamaran Sailors!

Sailing is probably the most gear-intensive activity I've ever done; there are so many decisions to be made about what gear to buy now, for tomorrow, and what to definitely never buy. The gear on...

6 Best Trailerable Trimarans For Bluewater and Coastal Sailing

Having a boat costs a lot of money, even when you are not using it, marina fees, etc. And once it is in the water most sailors never go very far from their "home marina" and sailing will be somewhat...

Logo

  • No products in the cart.

Catamarans and Trimarans

Catamaran and Trimaran Boat Plans make it a reality to build your own catamaran or trimaran. Multi-hulled sailing vessels are a special class of boat. A very different mind set is required when thinking about sailing a multi hull, let alone getting your head around building one.

There are some unique challenges building a multi-hull sail boat, the extra beam added by each hull for instance can create storage issues while under construction. Hartley boat plans make the build process straight forward for even amateur builders. However with all things considered, building a multi can be an amazing journey.

catamaran hull plan

Fast Twin Catermaran

catamaran hull plan

Lively 28 Cruising Trimaran

catamaran hull plan

Lively 35 Cruising Trimaran

Catamaran Plans Sun Set

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.

catamaran hull plan

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.

catamaran hull plan

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.

catamaran hull plan

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.

catamaran hull plan

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.

catamaran hull plan

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!

Leave a Comment Cancel Reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

[email protected]

Schionning Designs International Pty Ltd Leaders in Multihull Design and Kit Development.

Category: Our Catamaran Build Kits

Recommended equipment.

Catamaran Kit Materials. What do I receive? Schionning Designs supply a list of the Kit Materials you will receive to start the process.

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.

Schionning recommend equipment of Oceanvolt Ltd HYBRID AND ELECTRIC MARINE POWER AND PROPULSION SYSTEMS

Visit:  https://oceanvolt.com

Batteries, Power Management

Schionning Designs Recommend LIthium Lab suppliers of 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..

catamaran hull plan

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?

Superlight Balsa - End-Grain Balsa - Foam - Paper Honeycomb - Western Red Cedar - SDI - End-Grain Balsa - 150kg per cubic metre Paper Honeycomb - 50kg per cubic metre Superlight Balsa - 94kg per cubic metre Western Red Cedar - 360-380kg per cubic metre - Foam

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.

Schionning Catamaran Kit Materials contain Kinetix Laminating Resin & Hardener Kinetix Laminating resin is used on all of our designs and is used for laminating the strip-planked areas, so round-bilge designs will use it more often whereas our flat panel designs not as much.

KINETIX LAMINATING RESIN & HARDENER

Resin Choices for Catamaran Kit Building by Schionning Designs SDI - We choose ATL Composite's resin systems for their superior quality, reliability and value for money. West System Epoxy Resins

WEST SYSTEM EPOXY RESINS

Fibreglass Tapes (Double Bias) These double bias fibreglass tape rolls are used for the joining of panels in our flat panel designs, or in round-bilge designs to a lesser extent. Anywhere that DuFlex panels need to be joined, tapes will be used. The smaller rolls come in different widths for ease of use and to save time on cutting larger rolls of cloth.

FIBREGLASS TAPES (DOUBLE BIAS)

Schionning Designs Catamaran Kit Materials Carbon Fibre Cloth Carbon fibre is used on a number of our designs and can be incorporated into any design to save on weight and increase the performance capabilities. Carbon comes in unidrectional and double bias, however is much more expensive than standard fibreglass (as one might expect). It is very similar to work with, however the resin choice may change when using carbon.

CARBON FIBRE CLOTH

Schionning Designs Catamaran Design Kit Materials Fibreglass Cloth Fibreglass cloth is the strength and stiffness that holds your boat together, this is used in most areas for strength and is used in a variety of techniques depending on the area or job that is being performed. Fibreglass is one of the most widely used materials for low weight and high strength properties.

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.

Schionning Designs Catamaran Kit Build Process - Step 1 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 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.

Step 2 pre-cut frame panels are erected along the strongback in sequence - catamaran building step 2 SDI

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.

Step 8 catamaran kit building - forward webs and dash will be fitted - SDI

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.

Catamaran Kit Building Processs by Schionning Designs SDI -Step 9 The internal furniture is now installed, if you chose Kit Option 2, this furniture will be pre-cut to your previously decided upon layout. If you chose to receive blank panels, this is the period in which your internal living areas are to be built. This construction uses paper-honeycomb Duflex panels, as these are superior in weight when used non-structurally. Cabin soles, engines and daggerboard cases are also now installed.

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.

Resin Choices for Catamaran Kit Building by Schionning Designs SDI - We choose ATL Composite's resin systems for their superior quality, reliability and value for money.

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.

Colan brand cloths for their quality and low resin absorption - Schionning Designs SDI - We prefer Colan brand cloths for their quality and low resin absorption, custom made for Schionning Marine at six (6) stitches per square inch for easy wet-out and rounding corners.

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?

Superlight Balsa - End-Grain Balsa - Foam - Paper Honeycomb - Western Red Cedar - SDI - End-Grain Balsa - 150kg per cubic metre Paper Honeycomb - 50kg per cubic metre Superlight Balsa - 94kg per cubic metre Western Red Cedar - 360-380kg per cubic metre - Foam

  • 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!

HOME / INDEX PAGE  

Did You Know That We Offer Contract to Closing Services? Click Here to Find Out More.

Need Marine Financing? Apply Here With Our Partner, First Approval Source

  • Catamaran Interviews
  • Catamaran Reviews
  • Buying Advice
  • Selling Advice
  • Woods Design Advice
  • Americat 3014
  • Balance 526
  • Bali 40 Catspace
  • Beneteau Blue II
  • Broadblue 346
  • Broadblue 38 Prestige
  • Broadblue 385
  • Broadblue 435
  • Broadblue 46
  • Catalac 10M
  • Catalac 11M
  • Catalac 12M
  • Catalac 900
  • Catana 42 S
  • Chris White 48 Voyager
  • Chris White 55
  • Corsair F28 R
  • De Villiers
  • Dolphin 460
  • Endeavour 30
  • Endeavour 35 Victory
  • Endeavour 36
  • Endeavour 44
  • Endeavour 44 TrawlerCat
  • Fortuna 36 Island Spirit
  • Fortuna 401 Island Spirit
  • FP 32 Maldives
  • FP 35 Tobago
  • FP 37 Antigua
  • FP 38 Athena
  • FP 39 Fidji
  • FP 40 Lavezzi
  • FP 40 Lucia
  • FP 40 Summerland MY
  • FP 41 Lipari
  • FP 42 Astrea
  • FP 42 Venezia
  • FP 43 Belize
  • FP 44 Helia
  • FP 44 Orana
  • FP 46 Bahia
  • FP 46 Casamance
  • FP 48 Salina
  • FP 56 Marquises
  • FP 57 Sanya
  • FP 60 Eleuthera
  • FP Saona 47
  • Gemini 3000
  • Gemini 3200
  • Gemini 3400
  • Grainger 420 Mystery Cove
  • Hirondelle 7M
  • Lagoon 37 TPI
  • Lagoon 42 TPI
  • Lagoon 43 PC
  • Leopard 39 PowerCat
  • Leopard 45 Classic
  • Leopard 47 PowerCat
  • Leopard 51 PowerCat
  • Leopard 53 PowerCat
  • Maine Cat 30
  • Maine Cat 41
  • Matrix 450 Vision
  • Matrix 760 Silhouette
  • Maverick 400
  • Maverick 420
  • Maverick 440
  • Nautitech 40
  • Nautitech 442
  • Nautitech 46 Open
  • Nautitech 47
  • Outremer 40
  • Outremer 45
  • Outremer 50 Standard
  • Outremer 55
  • Privilege 37
  • Privilege 39
  • Privilege 42
  • Privilege 43
  • Privilege 435
  • Privilege 45
  • Privilege 465
  • Privilege 48 Transcat
  • Privilege 482
  • Privilege Serie 5
  • Prout 31 Quest
  • Prout 33 Quest
  • Prout 34 Event
  • Prout 35 Snowgoose
  • Prout 37 Snowgoose
  • Prout 37 Snowgoose Elite
  • Prout 38 Manta
  • Prout 39 Escale
  • Royal Cape 45
  • Royal Cape 530 Majestic
  • Royal Cape Majestic 500
  • Sailcraft 30 Iroquois
  • Sailcraft 32 Comanche
  • Sailcraft 35 Cherokee
  • Sailcraft 41 Apache
  • Sailcraft 44 Apache
  • Wildcat 350
  • Seawind 1000
  • Seawind 1160
  • Seawind 1200
  • Seawind 1260
  • Seawind 1600
  • Solaris 36 Sunrise
  • Solaris 36 Sunstar
  • St Francis 44
  • St Francis 48
  • St Francis 50
  • Stealth 11.8
  • Heavenly Twins 26
  • Ocean Twins 38
  • Voyage 380 Maxim
  • Voyage 400 Norseman
  • Voyage 430 Norseman
  • Voyage 450 Cabriolet
  • Voyage 47 Mayotte
  • Wharram 38 Tiki
  • AMI 320 Renaissance
  • Woods 22 Wizard
  • Woods 35 Banshee
  • Woods 35 Flica
  • Woods 36 Scylla
  • Woods 36 Vardo
  • Woods 38 Transit
  • Woods 40 Meander
  • Xquisite X5
  • Xquisite X5+

Catamaran Design Formulas

  • Post author By Rick
  • Post date June 29, 2010
  • 10 Comments on Catamaran Design Formulas

catamaran hull plan

Part 2: W ith permission from Terho Halme – Naval Architect

While Part 1 showcased design comments from Richard Woods , this second webpage on catamaran design is from a paper on “How to dimension a sailing catamaran”, written by the Finnish boat designer, Terho Halme. I found his paper easy to follow and all the Catamaran hull design equations were in one place.  Terho was kind enough to grant permission to reproduce his work here.

Below are basic equations and parameters of catamaran design, courtesy of Terho Halme. There are also a few references from ISO boat standards. The first step of catamaran design is to decide the length of the boat and her purpose. Then we’ll try to optimize other dimensions, to give her decent performance. All dimensions on this page are metric, linear dimensions are in meters (m), areas are in square meters (m2), displacement volumes in cubic meters (m3), masses (displacement, weight) are in kilograms (kg), forces in Newton’s (N), powers in kilowatts (kW) and speeds in knots. 

Please see our catamarans for sale by owner page if you are looking for great deals on affordable catamarans sold directly by their owners.

Length, Draft and Beam

There are two major dimensions of a boat hull: The length of the hull L H  and length of waterline L WL  . The following consist of arbitrary values to illustrate a calculated example. 

L H  = 12.20      L WL  = 12.00

catamaran hull plan

After deciding how big a boat we want we next enter the length/beam ratio of each hull, L BR . Heavy boats have low value and light racers high value. L BR  below “8” leads to increased wave making and this should be avoided. Lower values increase loading capacity. Normal L BR  for a cruiser is somewhere between 9 and 12. L BR  has a definitive effect on boat displacement estimate.  

  • Tags Buying Advice , Catamaran Designers

Rick

Owner of a Catalac 8M and Catamaransite webmaster.

10 replies on “Catamaran Design Formulas”

Im working though these formuals to help in the conversion of a cat from diesel to electric. Range, Speed, effect of extra weight on the boat….. Im having a bit of trouble with the B_TR. First off what is it? You don’t call it out as to what it is anywhere that i could find. Second its listed as B TR = B WL / T c but then directly after that you have T c = B WL / B TR. these two equasion are circular….

Yes, I noted the same thing. I guess that TR means resistance.

I am new here and very intetested to continue the discussion! I believe that TR had to be looked at as in Btr (small letter = underscore). B = beam, t= draft and r (I believe) = ratio! As in Lbr, here it is Btr = Beam to draft ratio! This goes along with the further elaboration on the subject! Let me know if I am wrong! Regards PETER

I posted the author’s contact info. You have to contact him as he’s not going to answer here. – Rick

Thank you these formulas as I am planning a catamaran hull/ house boat. The planned length will be about thirty six ft. In length. This will help me in this new venture.

You have to ask the author. His link was above. https://www.facebook.com/terho.halme

I understood everything, accept nothing makes sense from Cm=Am/Tc*Bwl. Almost all equations from here on after is basically the answer to the dividend being divided into itself, which gives a constant answer of “1”. What am I missing? I contacted the original author on Facebook, but due to Facebook regulations, he’s bound never to receive it.

Hi Brian, B WL is the maximum hull breadth at the waterline and Tc is the maximum draft.

The equation B TW = B WL/Tc can be rearranged by multiplying both sides of the equation by Tc:

B TW * Tc = Tc * B WL / Tc

On the right hand side the Tc on the top is divided by the Tc on the bottom so the equal 1 and can both be crossed out.

Then divide both sides by B TW:

Cross out that B TW when it is on the top and the bottom and you get the new equation:

Tc = B WL/ B TW

Thank you all for this very useful article

Parfait j aimerais participer à une formation en ligne (perfect I would like to participate in an online training)

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

TRI-STAR 24

Tri-star 25.

TRI-STAR 25 Study Plans $40.00 Add To Cart TRI-STAR 25 Plans $550.00 Add To Cart

TRI-STAR 26 MT

Tri-star 27-9, tri-star 31, tri-star 31 cm.

TRI-STAR 31CM Study Plans $40.00 Add To Cart TRI-STAR 31CM Plans $600.00 Add To Cart

TRI-STAR 32 XR

TRI-STAR 32XR Study Plans $40.00 Add To Cart TRI-STAR 32XR Plans $600.00 Add To Cart

TRI-STAR 35

TRI-STAR 35 Study Plans $ 40.00 Add To Cart TRI-STAR 35 Plans $ 650.00 Add To Cart

TRI-STAR 35 XR

TRI-STAR 35 XR Study Plans $40.00 Add To Cart TRI-STAR 35 XR Plans $700.00 Add To Cart

TRI-STAR 36

Tri-star 37 xrc.

TRI-STAR 37 XRC Study Plans $ 40.00 Add To Cart TRI-STAR 37 XRC Plans $ 800.00 Add To Cart

TRI-STAR 38 / 39

Tri-star 40 lw, tri-star 42, tri-star 43 xrc, tri-star 43 mc, tri-star 44 lw, tri-star 45, tri-star 49, tri-star 50, tri-star 51 mc, tri-star 54, tri-star 60 / 63, tri-star 65, tri-star 80, tri-star 104.

Email us for availability and prices

catamaran hull plan

MIKE WALLER 

Yacht design, multihull boat plans by mike waller yacht designer.

TC670 TRAILER CAT This is an all plywood, trailerable, of the beach sailing cat designed for sheltered and semi-sheltered waters. The cabin has a double berth, a galley, small table area and W.C.

tc670_16.jpg

TC750 CATAMARAN This all plywood cat is a larger and more able development of the 670, and being wider, is capable of more extensive adventuring.

W880 CATAMARAN This true ocean going little cat sleeps 4 and is built in strip plank cedar and glass composite, and plywood. Sleeps 4, and has a seperate WC / shower area.

w880 (1) - Copy.jpg

W1100 CATAMARAN This Ocean cruising vessel is in all plywood, and is capable of extensive ocean voyaging. Sleeps 5 in three seperate cabins, with seperate W.C / shower area.

W1160 CATAMARAN This ocean crusing family cat is built from strip plank cedar and glass composite. She sleeps 5 in 3 cabins and has a seperate WC / shower area.

w1160_01.jpg

W1200 CATAMARAN This ocean cruising family cat is a plywood version of the 1160, with rounded, strip planked hull bottoms and the rest of the boat in plywood. The transom is slightly extended to provide a wider boarding step.

W1350 CATAMARAN This is a family cruiser in cedar/foam/glass composite, intended for world cruising for a couple or small family

Profile 2_0001.jpg

W1480 CATAMARAN This is a true, proven, live aboard world cruiser for a family of up to 6 in four cabins. The vessel is strongly constructed in strip plank cedar and glass composite, and plywood. She will take you anywhere.

CS25 CATAMARAN This little demountable cat has two seperate hulls, each with two berths. She is all plywood.

cs25_01.jpg

CS35 CATAMARAN This cat has two seperate hulls with V shaped truncated sections, each has a double berth. She is all plywood and has a center cockpit which can be built in to form a shelter cuddy.

CC31 CATAMARAN This full bridge deck cat is in multi-chine plywood, and has two huge double berths, a dinette and seperate WC / shower area

cc31_02.jpg

CC40 CATAMARAN This ocean voyaging cat is in multi-chine plywood, and has two seperate hulls, a center cockpit with cuddy, and unbelievable accomodation for a vessel of this type and size

Log in or Sign up

You are using an out of date browser. It may not display this or other websites correctly. You should upgrade or use an alternative browser .

Open Source 13-15m Catamaran Plans

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

archie1492

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

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

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

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

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

Gene-Hull Catamaran 2.3 User Guide_2018 01 16.pdf

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

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

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

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.  

Open Trawler

The Open Trawler Project!

  • No, create an account now.
  • Yes, my password is:
  • Forgot your password?

Boat Design Net

Design Dynamics

Open Bridgedeck Catamaran

Configuration & Basic Types

Amultihull, just as any other type of boat, presents a series of compromises, and this applies to overall hull, deck and configuration as well. Concessions often have to be made because of space, performance or construction costs. In addition, the intended usage will be a significant factor in determining the shape and size of the vessel. Successful cruising designs will balance all parameters and only you, as a sailor, will know which type of catamaran will be suitable for your needs.

A monohull 's characteristics, largely determined by the beam-to-length ratio of the hull and its displacement, will vary very little from another ballasted boat, as there is only so much volume you can fit into a single hull. This will establish the amount of accommodations, which will not greatly differ from one monohull to another, setting a stark contrast to a catamaran, where intended parameters vary so much more.

Basically, we can break down the major design considerations into: overall configuration,

If one thinks of an open bridgedeck-type of catamaran, images of Hobie Cats on one end of the spectrum, and giant-open ocean racing multihulls on the extreme end, come to mind. They have no fixed coachhouse roof and some of them, especially the small beach cats, only have nets strung between the hulls. Larger examples have partial composite platforms, which stiffen the structure and allow for cockpit seats and helm stations. Since without a solid coachhouse there is less boat to build, these multihulls will be generally lighter and have better aerodynamic properties than full bridgedeck-type cats.

Although few manufacturers and designers have attempted to build open bridgedeck catamarans for cruising, only the most die-hard campers will find them useful for liveaboard applications. Typical examples are the older MacGregor 36, Stiletto 27 and 30, the French KL27 and Corneel designs, which could be sailed hard by lifting a hull (something that you try to avoid when cruising with a fully decked-out boat). Some of these vessels even featured a tiny removable doghouse which provided some shelter for the crew. On smaller open bridgedeck multihulls the only living quarters are found in the confines of the hulls. Even on larger types, they are cramped and not conducive to long-term cruising. The advantages of these sporty vessels,

Copyright © 2006, 2008 by Gregor Tarjan. Click here for terms of use.

Basic Catamaran Configurations

catamaran hull plan

especially in sizes below 30 feet, is their lower cost, trailerability and lively performance. However, attention has to be paid that they not be overloaded or else one could easily turn a cat into a t they are big moneymakers and are considered the workhorses of the sea.

A large exception to the class 1 type of configuration is found in sizes above 30 feet, which could be considered as class 2. Manufacturers such as Maine Cat and a few other custom multihulls such as the Shuttleworth successfully combine an open-deck plan with a certain degree of cruising comfort. In order to provide some shelter for the crew, large semi-rigid biminis are erected. Not only are these afterthoughts unsightly and do no justice to the beauty of these boats, but they also add a considerable amount of drag, contradicting the nature of these athletic multihulls.

Large charter boats or "Day Boats," as they are called, also utilize the open bridgedeck layout to maximize cockpit space. These machines can entertain up to 80 passengers and are found in holiday resorts around the world. Correctly managed and marketed,

Partial Bridgedeck Catamaran

These are often referred to as cruising/ racing types and, unfortunately, very few existing manufacturers still make them. Designs such as the older Edel and Outremer catamarans had a rigid deck and a small coachhouse, which was completely separate from the hulls. My own Outremer 43 "Flo" was of that category. She was a great sailboat and provided ample room for our family cruises along the U.S. East Coast. Similar to the class 1 vessels, the bridge decks of these types of catamarans are also shorter fore and aft, and the accommodations are simple.

Partial bridgedeck catamarans usually place simple sitting arrangements and nav-stations on the main deck. The balance of the layout, below The Broadblue range of cruising catamarans are examples of full-length bridgedeck multihulls, providing plenty of volume for cruisers.

Catamarans Design

above The Blubay 72 is a state-of-the-art, maxi-sized racer-cruiser featuring a separate saloon pod. She will cruise at close to 28 knots.

below The Gemini 105Mc, seen here in the Patagonian channels, is a popular full bridgedeck catamaran which, in capable hands, can be taken to the world's most remote areas.

such as the galley, heads and berths are often situated in the hulls. Most of the time, these multihulls only have sitting or crouching headroom in the saloon, unless the cabin sole is dropped significantly, compromising the underwing clearance. The Edel 35 was particularly notorious for her low bridge deck, although hundreds of them were built.

Edel Open Deck

Advantages are good looks and light weight overall structure, but the fact that one can only access the hull compartments via the cockpit poses limitations for serious cruising or live-aboard applications.

Some years ago when Outremer was looking for a substitute for its 40 footer, I was asked to design an open bridgedeck type and came up with a compact 38' racer/cruiser with low profile and tiller steering. Unfortunately, lack of demand prevented the project from being realized and the Outremer 42 was born. However, I feel that a properly designed class 2 multihull is a fantastic compromise for the average weekend sailor. It is unfortunate that presently no manufacturer builds one.

Bridgedeck Catamaran

Probably the majority of production and custom cruising catamarans belong to this category, which is the focus of this book. A bridgedeck multihull maximizes the use of space and features a solid deck with a coachhouse that spans the entire width of the cockpit. There is one main entrance into the boat via large sliding doors, and access into both hulls is through companionways leading down from either side of the large saloon. Bridgedeck catamarans are ideal for cruisers or liveaboard sailors. These vessels feature ample payload-carrying capacity and provide good protection for the crew. Helm locations are usually behind the coach roof bulkhead or in some rare cases on the aft end of the hulls behind the cockpit.

These class 3 multihulls contain all the comforts of home and feature a spacious

Catamarans Design

saloon, galley, and navigation station on the main deck. The coachhouse acts as a centralized core, spanning both hulls, which are usually reserved for heads, sleeping cabins and storage. Unlike any other type of boat, monohull and multihull combined, the class 3 cruising catamaran has an unrivalled "homey" feel to it. The wide cockpits are protected by biminis which integrate seamlessly into the coachroof. This not only looks good but creates an inside-outside space that is both practical and unique.

Large bridgedeck cats have the capacity and volume to carry most of the items you would find in your home. From dishwashers to the generators that power them, you can actually have it all. However, the desire to load up too much sometimes overburdens the vessel, compromising its performance.

On vessels larger than 40 feet, headroom is sufficient, although individuals 6 feet and taller might have to make compromises in the forward part of the saloon or in the extremities of the hulls. Designers try to balance the need for ample bridgedeck clearance and place the cabin sole high enough to avoid underwing pounding created by waves. Low, good-looking silhouettes can be found on larger catamarans, although some manufacturers have the "no holds barred" approach and make their boats look like a toolbox. Although this maximizes space, the chunky appearance is detrimental to the performance of the boat as it increases air drag. Finally, square coachhouses make catamarans look rather unattractive.

Some builders elect to pull the solid bridge deck all the way from bow to stern.

above This recently launched Yapluka 72' catamaran is seen here in full cruising trim and serves her owner-couple as a liveaboard world voyager and mobile office.

Bridgedeck pounding caused by waves is one of the drawbacks of low underwing catamarans. Moderate displacement, full-volume bow and stern sections, and a high and long bridgedeck will minimize, if not eliminate, annoying wave slap under the saloon sole. Although bridgedeck height is a very important parameter, it is a misconception that it is the only design feature to look for. One has to consider weight as well as its distribution and support by the hulls, especially in the extremities. Heavy, low bridgedeck multihulls might make great liveaboard vessels, but they should only be taken to sea by masochists.

below A partial bridgedeck cat, such as the older Outremer 43, was a swift boat but had the disadvantage of separate saloon and hull access.

Parameters Contributing to Bridgedeck Pounding

catamaran hull plan

This book would not be complete without the mention of the new breed of luxury yacht: the Multihull Supercat. These magnificent vessels usually measure in

Multihull Boat Plans Free

This is beneficial for stiffening the structure and making the most out of the available deck space. The Gemini catamaran is a very successful design which employs this layout. Yet designers who try to put too much weight into the ends must be careful. These types frequently suffer from excessive pitching in a seaway and display mediocre performance under sail.

Superyacht Catamaran

This book would not be complete without the mention of the new breed of luxury yacht: the Multihull Supercat. These magnificent vessels usually measure in excess of 100' and can sail on free wind energy at more than 30 knots without any heel. They feature living rooms the size as found on monohull superyachts twice their size, and require neither a dozen crew to run them nor large diesel engines. Very few builders in the world specialize in these types of vessels, yet their ideal application as large eco-expedition vessels, corporate entertainment platforms, or ultimate private yachts is unquestionable. Blubay Yachts of France seems to be on the forefront of this group as they have gained invaluable experience by being the only builder that has built a succession of composite superyacht multihulls upwards of 100'.

The world market for extravagant pleasure boats has been steadily growing, yet the catamaran platform for luxury sailing vessels has only recently been recognized.

Modern composite materials and highlevel engineering utilizing Finite Element Analysis now permit the construction of large structures such as multihulls, which was not possible 10 or 20 years ago. The aeronautical and automobile racing industry have contributed considerably to the design and engineering of complex composite structures from which super-catamarans have greatly benefited. The use of aluminum has been the classic hull and superstructure material for large vessels around 60' and it is still a strong and economical build alternative. With the advance of composite technology experienced builders (usually French yards) are developing lighter, stronger and increasingly sophisticated super-yachts, providing clients alternatives that were unheard of just years ago.

Large catamarans, with their wide and stable platforms are becoming recognized as ideal structures for lavish, as well as exciting, pleasure boats. Their vast living accommodations and privacy layout make them ideal for people looking for an alternative to deep draft and heavy monohulls. In addition, their low-profile underbodies permit access to shallow harbors. The new generation of research vessels and oceanographic laboratory ships are frequently large catamarans. They project the image of eco-friendliness and efficiency as they are propelled by clean wind energy. Their shallow draft allows access to reefs and remote anchorages. Their wide aft platforms provide superior storage facilities for large dive tenders and even ideal helicopter landing pads. The demand for these types of superyacht catamarans worldwide is steadily growing.

below Large luxury yachts, such as this 100' catamaran, can easily accommodate several dozens of guests in ultimate comfort while, at the same time, they can sail at double-digit speeds. With world oil prices steadily rising, they very well might become the new breed of mega-yacht.

Mega Catamaran Yachts

Continue reading here: Catamaran Design Guide

Was this article helpful?

Recommended Programs

Myboatplans 518 Boat Plans

Myboatplans 518 Boat Plans

Boat Alert Hull ID History Search

Boat Alert Hull ID History Search

3D Boat Design Software Package

3D Boat Design Software Package

Related Posts

  • How Much Payload Do A Cruizing Catamaran Need
  • Bridge Clearance - Maintaining Boats
  • How Are Catamaran Masts Fixed Down
  • Configuration Types - Catamarans Guide
  • Hull Hydrodynamics and Design

Readers' Questions

How to build a catamaran free plans?
There are a number of online sources that provide free plans for building a catamaran, such as: The Boat Plans Collection: <a href="http://www.theboatplanscollection.com/catamaran-plans/" >http://www.theboatplanscollection.com/catamaran-plans/</a> Boat Design Net: <a href="https://www.boatdesign.net/forums/multihulls/free-catamaran-plans-54219.html" >https://www.boatdesign.net/forums/multihulls/free-catamaran-plans-54219.html</a> DIYCatamaran: <a href="https://www.diylargecatamaran.com/category/plans/" >https://www.diylargecatamaran.com/category/plans/</a> Multihulls 4 U: <a href="https://www.multihulls4u.com/diy-catamaran-plans/" >https://www.multihulls4u.com/diy-catamaran-plans/</a> BoatBuilderCentral: <a href="https://boatbuildercentral.com/category/boat-plans/power-catamaran.html" >https://boatbuildercentral.com/category/boat-plans/power-catamaran.html</a> Before beginning the project, be sure to read and understand all instructions, diagrams, and safety guidelines that are included in the plans. Additionally, consider consulting with a professional boat builder in the case of any questions or doubts.

Boating.Guide - Everything you want to know about boating.

A Trusted Source For Boating Information Since 2019

Catamaran hulls- everything you need to know.

  • Post Written By: Boater Jer
  • Published: July 17, 2022
  • Updated: July 19, 2022

Catamaran Hulls- Everything you need to know at Boating.Guide.

Disclaimer: You might notice that we recommend products in some articles. We may earn a commission for referring you if you click the link and buy a product.

We only recommend products we’ve tried/tested/own (that’s why you won’t find thousands of affiliate links on my site). If you have experience with one of the products we’ve mentioned, please share your experiences in the comments at the end.

Advertisement

Top-rated trolling motors on Amazon

Catamaran hulls are not like normal boats but provide increased stability. Let’s take a look at these incredible boats and how their hulls create one of the most versatile watercraft available today.

The Tamil Cholas used catamarans to ferry their troops to invade Malaysia, Indonesia, and Burma. The early paravars or fishing communities in the southern part of Tamil Nadu used two-hulled boats to fish. Polynesian seafarers were also early users of the catamaran, utilizing the watercraft to get to hard-to-reach islands. ( source )

Although the catamaran hull concept is a relatively new introduction to modern boat design , the boat has been in use since the 5th century. It was used for fishing, traveling, and transporting people and supplies. 

Parts Of A Catamaran

Here are the basic parts of the modern sailing catamaran:

  • Hulls are what sets this boat apart from the rest. The catamaran has two hulls, while the monohull, as the name suggests, has only one hull. Most of the advantages of this boat are hinged on these two hulls. 
  • The bridge deck connects the two catamaran hulls. 
  • On top of the catamaran hulls and the bridge deck is the deck . It is where owners attach most of the equipment in a boat. 
  • You can locate the berth, the galley, and other living amenities in the cabin . 
  • The cockpit is where you find the navigation equipment of the boat . It is where you control the catamaran’s rudder, sails, and engine. 

Types Of Catamaran

Types of catamarans are explained on Boating.guide

The modern catamaran is far more different than its crude ancestor. Instead of tree cutouts, catamarans are now carbon fiber or fiberglass. Here are the different types of catamarans: 

Top-rated fish finders on Amazon

Based On function

Pontoons are usually present on rivers and lakes and sometimes even on oceans, but they only travel near the shore.

In a catamaran pontoon-type boat, the pontoons serve as storage areas, where you will find the onboard motors. They are useful for water leisure activities such as short water trips, tubing, wakeboarding, and water skiing. 

Some pontoons may also serve as houseboats. They provide a broader, more stable platform ideal for a floating house. Plus, the space is bigger, and most of it is above water. It offers a better viewing option than a monohull. ( Source )

Small Waterplane Area Twin Hull is a catamaran-type boat that the United States Navy initially used for military purposes. They provide the water stability that is necessary when transporting heavy military equipment. 

One example of a military SWATH catamaran is the Spearhead class EPF. It is as long as a World War II escort destroyer, yet it is twice as fast at 43 knots. It can reach that speed because of its two separate hulls.

Because of their innate speed, SWATH catamarans can become patrol boats in lakes and rivers. They can easily outrun and outmaneuver standard watercraft.  

Nowadays, there are SWATH cruise ships and other non-military variations. ( Source )

Top-rated boat gps on Amazon

Based On Design

  • Sailing Catamaran

The smaller sailing catamarans do not have auxiliary engines, so the owner can propel the boat by harnessing the wind using the sails. It’s a popular choice for people with very little or no sailing experience because they are light and easy to use. 

The larger sailing catamarans are for group charters and long-distance cruising. They have become so popular lately that they now outnumber monohulls in tropical locations all over the world. They have a last, a headsail, and a mainsail. And the twin hulls have one engine each. 

  • Power Catamaran

Unlike their sailing cousins, the powered catamarans do not have sails. They have massive engines which provide high speed. Their twin hulls are stronger and can carry and protect the large motors. 

The smaller “powercats” are used mainly for fishing. The bigger ones are rented out for charters and cruises. 

Catamaran Hulls Performance 

Thanks to the catamaran hulls, the boat offers many advantages over other boat types. 

  • Because its dual-hull design provides a broader base, it offers more water stability than monohull boats. It makes the cat (catamaran) a popular choice for fishing expeditions and cruises.
  • Riding a catamaran is ideal for people who feel seasick whenever they ride boats. The twin hulls prevent the boat from moving from side to side. The hulls allow the boat to travel smoothly, even on moderately choppy waters.
  • The catamaran is the best choice when storing provisions and other household items with less heeling and bobbing. 
  • The twin hulls’ stability is ideal for many activities such as cooking and partying. 
  • Cats offer more moving space because of their broader base, thanks to dual hulls.
  • With a catamaran, you have two great options on where to hang out. You can do it on the spacious deck or below the galley. 
  • Compared to a monohull of the same size, the catamaran can accommodate more equipment and people.
  • The living area in a catamaran is above the water line. This feature provides more natural light, a greater view of the outside, and better air circulation. 
  • Since catamarans do not have keels, they can anchor on shallow waters, something that most monohulls will not be able to do. This ability of catamaran boats is impressive, especially if you are going around areas with many reefs and small islands.
  • Catamaran hulls allow the boat to cut through the waves easier and faster. It means they require less engine power than their monohull counterparts.
  • Because it has two engines and two rudders, the catamaran can easily maneuver in very tight spaces. 
  • Because they do not carry heavy keels, catamarans can sail faster than monohulls. 
  • The catamaran’s stability, speed, and weight make it a safer option than the monohull. It can sail in shallow waters, make a 360 degrees maneuver effortlessly, and carry more provisions. 

Disadvantages Of A Catamaran

Like any other boat type, the catamaran also has drawbacks and limitations. Here are some of them:

  • The catamaran hulls prevent the boat from sailing as fast as the monohull upwind. The two hulls cause drag, and this slows the boat considerably. 
  • Because of its bigger size, looking for a docking site can be more difficult and costlier than a monohull. 
  • For hardcore sailing fans, the experience of sailing with a catamaran will never be able to match that of sailing with a monohull. To them, the challenge of true sailing is just not there with a catamaran.

What Are The Hulls Of The Catamaran Called?

According to the Online Etymology Dictionary, the Tamil word கட்டுமரம், which is pronounced as kattumaran, is where the word catamaran takes its name. The word means “pieces of logs tied together”. Through the years, the term has evolved into what is now a catamaran in English. 

Top-rated boat seats on Amazon

What Are The Characteristics Of A Catamaran Hull?

  • Both hulls of a catamaran complement each other to achieve very minimum water resistance. 
  • Because of this, it takes less energy to propel a catamaran, whether via an engine or sails. 
  • The catamaran hulls provide stability to the boat. The twin-hull significantly reduces bobbing. 
  • The catamaran’s ability to keep steady on the water makes it an ideal vessel for cooking, dining, and storing provisions. 

Are Catamarans Good In Rough Water?

Catamarans are amazingly stable in rough water. The catamaran’s design and build, which provides stability, are factors why it is one of the best boats to use when the waters are choppy. 

Yes, catamarans are relatively more expensive than monohulls. Nevertheless, since single-hull boats are less expensive, their resale value is also cheap. 

If you add all the advantages that a catamaran offers – safety, comfort, and speed- it does not come out expensive. 

patekphilippe.io

Top-rated kayak accessories on Amazon

Share this post with your friends

Subscribe to our newsletter.

Join us in our love for all things water. And Adventure.

Two men captain the helm of this large vessel with a massive steering wheel.

Why Are Boat Steering Wheels So Big?

Advertisement You see them on the water in summer or all year round, depending on where you live, boats, and lots of them. Riding on the water on a ship is calming and relaxing unless you are racing, then it can be exhilarating and action-filled! I have been on many boats of different shapes and

A painting of rough seas is shown in this file photo.

Are Catamarans Safe In Rough Seas?

Catamarans are known to be reliable and fun to operate. From the personal watercraft sized cats to the massive superyacht class of catamaran, all are great ships of the seas. But are catamarans safe in rough seas?

Pontoon boat vs catamaran explained at Boating.Guide.

Pontoon Boats Vs. Catamaran (Pros and Cons For New Buyers)

Advertisement Pontoon Boats Vs. Catamaran – Pros and Cons For New Buyers – A Boating Guide Buyer’s Guide For 2023. Would you like to know the differences between pontoon boats and catamarans? These two vessels seem similar in the hull design to stay on the water. However, there are several differences, and each ship is

A Flat-Bottomed Planing Hull Fishing Boat

Boat Hull Types – Which Boat Hull Is Best?

In this article, we examine all these hull types with full explanations of how each one works so you can figure out which is best suited for you.

Choosing your first boat, like the boat for sale in this image, is easier with the help of Boating.Guide Buyer's Guides.

A Guide To Choosing Your First Boat

Advertisement A Guide To Choosing Your First Boat – A Boating Guide Buyer’s Guide Report for 2023. Would you like to buy your first boat? When you buy a boat for the first time, it is easy to make a mistake due to the lack of experience. Therefore, before making any decision, you must evaluate

The PowerSeeker - An Intelligent Fish Finder of Tomorrow That's Here Today.

PowerSeeker Intelligent Fish Finder – A Smart Fishing Gadget

Advertisement PowerSeeker Intelligent Fish Finder Review Do you love fishing? Who doesn’t? Fishing is not an easy task, especially if you’re out on a trip with your friends. It’s because, at such times, it becomes a matter of pride to quickly catch a vast fish.  Mostly, people find it hard even to trace a fish.

catamaran hull plan

Boat Information By Type

© 2023 Boating.Guide, A Hyperwave Media Group Ltd. Publication.

Privacy Overview

  • PERFORMANCE TOPICS

Optimising Hull Lines for Performance

This article was inspired by a question about the rocker line in the new 8.5m cat Design 256 and I want to stick to the point, so we won’t turn it into a book, but I’ll discuss two issues, hull fineness ratio and some aspects of the rocker profile.

When you manipulate the hull form you’re adjusting the lines in three planes, waterplanes (plan view), buttocks (side view including the keel rocker) and the section shapes. So you need to be aware of how the shapes are changing in the other two planes as you manipulate any one of these three, or all three globally as is now possible with computer modelling.

There are two fundamental constants that you start with and don’t change throughout the process. The big one is the displacement or the amount of buoyancy you need.

If you make the hull finer by narrowing the waterlines you have to increase the draft or make the ends fuller to get back to the required displacement number.

If you flatten the rocker line you have to increase the hull width, fill out the ends, or square up the section shapes rather than having a V or rounded V. 

The other constant is the longitudinal centre of buoyancy. You really can’t do any meaningful shaping of the hull form until you have settled on the these two constants.

A third number that we can plug in as a constant if we want to is the prismatic coefficient which describes bow much volume there is end the ends relative to the cross section shape in the middle of the boat, but in sailing boats this is of less importance compared to other factors. 

Lines plan for the Livewire Catamaran

The hull lines for Design 256, 8.5m Cat. It's that hump in the rocker line - right under the back of the cabin that brought up the question and is one of the key points discussed here.

Hull fineness.

Fine hulls are fast, but only in the higher speed range. There’s a misconception I come across quite a bit that you can add weight and windage and you’ll still be fast as long as your hulls are fine.

Well you won’t be. Your boat will simply sink to find the new state of equilibrium. If your transoms are submerged you’ll have more drag. If your bridge deck is too close to the water you’ll have slamming. Much better to be conservative with your displacement figure in the design stage than overly optimistic.

And fine hulls have more wetted area so you have more drag in light air where friction resistance is the primary drag factor. 

I’ve seen promotional material for catamarans stating that the boat has less wetted area because it has fine hulls. For a given displacement the minimum wetted area is described by a sphere (or a semi sphere in the case of a floating object). The more you stretch it out in length, keeping the displacement constant, the more wetted area you have.

The more you make the section shape into a deep V or a broad U with tight corners, as opposed to a semicircle, the more wetted area you have. Add into the equation finer hulls are slower to tack.

So fine hulls are only an advantage if your boat is light and has enough sail area to ensure you’re travelling at speeds where form resistance is greater than skin resistance.

In my view the advantage of fine hulls is often overrated as it applies to cruising cats.

At the other end of the scale the resistance curve is fairly flat up to about 1:9 which is still quite fast in most conditions. From there the resistance rises steeply as the hull gets fatter and at 1:8 and fatter you’re suffering from some serious form drag.

Illustration of buoyancy distribution in catamaran hull

This is the rocker line isolated from the lines plan above (in blue) and and the red line shows a more moderate rocker line that achieves the same buoyancy and maintains the centre of buoyancy in the same position.  The bow is to the right.

In the image lower right I've squashed it up and increased the height to make the difference in the lines more obvious.

The difference in the two lines is quite subtle, but races are often won or lost by seconds.

Rocker Profile

So if we’re looking for low wetted area we would want a rocker profile that was even and rounded, relatively deep in the middle and rising smoothly to the surface at each end. But this would give us a low prismatic which is not ideal in the higher speed range, and it’s not ideal for pitch damping which in my view is the critical design factor that is often underrated. 

Pitching is slow. It destroys the airflow in your sails and the flow around the hulls, and your performance is suffering from slamming loads.

The single most effective way to counter pitching is with asymmetry in the water planes. You can achieve that in the with a fine bow and broad transom. Or you can achieve it with V sections forward and a flattened U shape aft. Or you can achieve it in the profile view with a very straight run forward and a bump in the aft sections. A flatter rocker line is better for resisting pitching than an evenly curved one with deeper draft in the middle.

The final result is a combination of all three of these factors.

On a cat like Design 256 the weight is concentrated well aft so we need to get buoyancy well aft.

The kink you see in the rocker profile helps to do this. It also helps to keep the rocker straight for most of its length and smooth the water flow exiting the hull aft at higher speeds, possibly promoting some planing effect.

If we had a more even rocker line we would slightly reduce the wetted area, but we would increase the pitching and the water would exit the hull aft at a steeper angle, increasing form drag in the higher speed range.

How much of a bump can you put in there without creating a flow separation, and how damaging would that flow separation be? I really don’t know. The way all of these factors interplay in the various conditions we sail in is very complex.

Ultimately a lot of this work is gut feel nurtured by experience, observing things in nature and most importantly experimenting and trying new ideas.

Is the new Groupama AC45 a breakthrough that will influence the form of racing catamarans into the future? I don’t think anyone has a computer that can answer that. We have to wait and see.

Catamaran hull lines showing symmetric and asymmetric waterplanes

Symmetric and non symmetric water-planes. The blue line with grey fill is the DWL from the design above. As is typical with modern cat hulls the bow is long and fine, the stern is full and rounded. This is the asymmetry that has a damping effect on pitching. The red line on the other hand is more like you would see on a double ended monohull and quite a few multihulls have also used this shape in the past. It's quite symmetric about the pitch axis and does not have good pitch resistance.

Lines plan for the Livewire 28 Catamaran

The hull lines of the new 8.5m Sports Cat Design 256

Lines plan for Mad Max Design 101

Mad Max , Previously Carbon Copy . She was designed in 1997 but she's the current (2016) title holder of the Australian Multihull Chamionships (2 successive years) and the fastest inshore racing boat in Australian waters.

Join the Newsletter

Custom and Racing Designs

  • Scroll to top
  • Aluminum Boat Plans

35 FT Catamaran Workboat (616)

36 x 12 cat 2.jpg (1)

This design (plan) is a 35 FT aluminum catamaran. Power is two (2) Volvo D4-225 DP I/O at 189 HP each.

Gross weight and speed dependent on final arrangement.

*The above price is for the construction plans and a onetime use of the CAD cutting files.

Weight in table above is the weight of the uncut aluminum sheet and plate.

Stock hull is the flush deck shown on the included PDF drawing. Cabin and bullwork are available options.

Cabin and bullwork is not included in the aluminum sheet and plate weight calculations.

Welcome to Lake

Discover places to stay and unique experiences around the world.

  • How It Works

listing icon

Home - Blog - Catamarans Uncovered: The Ultimate Guide to Dual-Hulled Sailing

Catamarans Uncovered: The Ultimate Guide to Dual-Hulled Sailing

David Ciccarelli

David Ciccarelli

January 27, 2024

In this article

Get started.

get_img

Understanding Catamarans

When you think of sailing through turquoise seas, what comes to your mind? If you’re picturing luxurious, spacious boats that glide smoothly over water, then you’re probably thinking of catamarans. These multi-hulled marvels are not your average boats; they’re about stability, space, and speed. Let’s set sail on understanding what makes them so unique.

Catamaran Basics

Catamarans are characterized by their two parallel hulls, which fundamentally distinguish them from the traditional monohull vessels. This twin-hull design often results in a wider beam, creating an inherently stable platform. While they boast a shallower draft compared to monohulls, catamarans generally provide more living space and less heeling. With less resistance in the water, performance catamarans can achieve greater speeds. The typical displacement of these vessels means they sit on top of the water rather than plowing through it, which adds to their efficiency.

Historical Evolution

The history of the catamaran dates back thousands of years, with its roots in the fishing and transportation crafts of the ancient Polynesians. Through generations, the design has evolved from simple canoes with outriggers to the sleek, modern vessels we see today. From rudimentary construction to high-tech materials, catamarans have adapted to become a favorite in both private and commercial sectors.

Types of Catamarans

If we list out the types of catamarans, you’d encounter various classes tailored to different sailing needs. You have your cruising catamarans, spacious and comfortable, ideal for those leisurely voyages. There’s the more agile performance catamarans, designed with speed and responsiveness in mind. And then, the luxury catamarans—think of these as floating mansions, complete with opulent amenities and furnishings.

Sailing Catamarans

Your sailing catamarans are akin to dancers on water. With sails harnessing the power of the wind, these vessels are all about eco-friendly propulsion and an authentic sailing experience . Imagine gliding past coastlines without a noise except for the wind in the sails and the water against the hulls. Brands like Lagoon and Fountaine Pajot have become synonymous with this category, providing a range of options from small day sailors to majestic cruisers.

Power Catamarans

Power catamarans, as the name suggests, rely on engines for movement. These are the go-to for those who prefer a bit more oomph in their voyage—capable of higher speeds and longer range without wind dependence. They’re perfect if you’re into coastal hopping or even deep-sea adventures.

Luxury Catamarans

Indulge yourself with luxury catamarans, the epitome of elegance on the water. These vessels come with full crews, gourmet meals, and the kind of pampering you’d expect at a 5-star resort. They represent the pinnacle in comfort and amenities , often custom-designed to meet the desires of the most discerning sailors.

Let’s pause for a breath—feeling the breeze yet? Catamarans are indeed a special breed of vessels that combine innovation, comfort, and performance. So next time you dream of sailing, think of these dual-hulled wonders and consider that perhaps your next adventure awaits on board a catamaran.

Catamaran Design and Construction

catamarans

Catamarans are unique in the boating world, offering stability, space, and speed that many sailors dream of. Whether you’re an enthusiast or a prospective buyer, understanding the intricacies of catamaran design and construction is essential. Have you ever wondered what goes into making these remarkable multihull vessels?

Multihull Structure

Multihull vessels, such as catamarans, are defined by their two separate hulls. This design provides natural stability which is excellent for reducing seasickness. A significant advantage here is safety ; with two hulls, even if one becomes flooded, the catamaran can often remain afloat and upright.

The Dual-Hull Design

The dual-hull design of catamarans allows for a wider beam, which translates into more deck space. When compared to monohulls, catamarans don’t heel over, making your experience onboard more comfortable and safer. This design also means less resistance when cutting through water, increasing your speed potential.

Advantages of Multihulls

Catamarans are renowned for their spaciousness and comfort, but did you know they tend to have a shallower draft? This allows you to easily explore shallower waters where other boats can’t go. Additionally, they are often faster, making them a favorite for both racing and cruising.

Materials and Construction

When building catamarans, manufacturers often utilize lightweight materials to enhance performance without compromising strength. Composites like fiberglass are common due to their durability and ease of maintenance .

Building Catamarans

The process of building catamarans involves meticulous planning and precision. Each step, from the initial design to the final touches, aims for a blend of performance and comfort. The popularity of DIY catamaran kits has also risen, catering to those who wish to take a hands-on approach to their vessel.

Composite vs. Aluminum

Catamarans can be built from various materials, but the debate often falls between composites and aluminum. Composites are prized for their strength-to-weight ratio, while aluminum is favored for its toughness and repairability. The choice depends on the intended use and the desired balance between weight and durability.

Rigging and Sails

The rigging and sails are critical in determining a catamaran’s performance. With more sail area, catamarans capture a greater amount of wind, which can improve speed. However, the sail plan must be carefully designed to balance power and handling .

Sail Configuration

Choosing the right sail configuration depends on your sailing needs. For travelers who prefer easier handling , a simple sloop rig with one mainsail and one foresail may suffice. Alternatively, performance-oriented sailors might opt for additional sails like spinnakers for downwind speed.

Sail Handling Systems

Modern catamarans incorporate advanced sail handling systems to make sailing more manageable, even for smaller crews. Features such as roller furling for the jib and lazy jacks for the mainsail simplify sail deployment and retrieval, which can be a real back saver!

So, have you gotten a clearer picture of what goes into a catamaran’s design and construction? Whether it’s the material selection or the intricacies of sail handling, each aspect plays a part in giving you the ultimate experience on the water.

Key Features and Advantages

catamarans2

When you’re in the market for a boat that embodies comfort and performance, a catamaran is hard to beat. Let’s dive into what makes these vessels a standout choice for sailors and how they might just be your ticket to the ultimate sailing adventure.

Stability and Safety

Catamarans are renowned for their stability on the water, which translates into increased safety during your maritime excursions. Thanks to their wide beams, which can significantly exceed those of monohulls, moments of discomfort from rolling are minimized whether you’re at anchor or cutting through the waves.

Reduced Risk of Capsizing

The dual hulls of a catamaran are not just for show; they inherently provide a lower center of gravity and a wider base, which greatly decreases the odds of capsizing, giving you peace of mind as you navigate various sea conditions.

Safe Sailing in Rough Waters

One of the greatest perks of catamarans is their capability to handle rough waters with aplomb. The vessel’s design allows for quick and responsive movement, which is crucial when you’re miles from shore and conditions become challenging.

Spaciousness and Comfort

A catamaran is synonymous with spaciousness. Due to the dual hull construction, you’ll find ample living spaces comparable to a floating apartment, making long passages or entertaining guests a delightful experience.

Ample Deck Space

Have you dreamed of a boat where you can lounge, dine, and play without feeling cramped? A catamaran’s deck provides generous outdoor living areas, perfect for soaking up the sun or enjoying al fresco meals with a view of the ocean’s expanse.

Comfortable Living Spaces

Below deck, catamarans boast comfortable living quarters with enough headroom and sizeable cabins . The separation between sleeping areas, often located in different hulls, also ensures privacy that’s hard to come by in other vessel types.

Speed and Efficiency

With a sleek design and lighter weight, catamarans can glide through water quickly and with less effort. Their speed capability is not just great for thrill-seekers but also for those who wish to cover significant distances in tighter timeframes.

Fuel Efficiency in Power Catamarans

For power catamaran lovers, the efficiency game is strong. These cats are designed to consume less fuel while maintaining speed, leading to long-term savings and a reduced environmental footprint.

Ocean Cruising Capabilities

A catamaran truly shines when it comes to blue water cruising. The vessel’s stability and performance make this type of boat well-suited for exploring a variety of destinations across the globe.

Long-Distance Cruising Comfort

Planning an overnight or multi-day cruise? Catamarans are equipped to provide exceptional comfort during long-distance journeys, allowing you to reach far-off places like the Caribbean or South Pacific with ease and pleasure.

Catamarans for World Travel

Imagine setting sail to any corner of the world in a boat that feels like home. Catamarans offer that potential with their excellent cruising capabilities, capacity for provisions and fuel, and comfort—making them ideal for the adventurous sailor eager to chart a course for exotic destinations.

Remember, catamarans by brands like Lagoon or Fountaine Pajot are not only a statement of luxury but also showcase the pinnacle of marine engineering designed with your sailing lifestyle in mind. Ready to catch the wind in your sails?

Notable Catamaran Brands and Models

catamarans4

When you’re out on the open waters, the brand and model of your catamaran are as important as the wind in your sails. Let’s talk about some of the most revered names that have made waves in the world of catamarans.

Lagoon Catamarans

Lagoon is a French manufacturer that’s taken the catamaran market by storm. Known for a blend of innovation and tradition, these catamarans have a strong global presence.

Since its inception in 1984, Lagoon has become synonymous with high-quality catamaran craftsmanship. Their journey began as a segment of the illustrious Group Beneteau, sailing onto becoming a standalone brand admired by many.

Fountaine Pajot

Fountaine Pajot , another French marvel, has carved its niche in the luxury catamaran market since 1976, delivering elegance and sturdiness in every vessel.

Awarded multiple times, including ‘Boat of the Year’, Fountaine Pajot’s reputation is built on innovation, performance, and eco-friendly designs. They are a marquee name for discerning sailors looking for the French touch in boating excellence.

Leopard Catamarans

South African-built Leopard Catamarans offer a robust build quality and a luxury cruising experience that appeals to adventurers and comfort-seekers alike.

Leopard has consolidated its status in the catamaran domain with models like the Leopard 48, known for its innovative design and exceptional onboard amenities.

In your quest for the perfect catamaran, these brands and models stand as shining beacons of quality and expertise. Each one has a story to tell and a journey to offer, ready to make your seafaring dreams a reality. Which one will you choose for your next maritime adventure?

Choosing the Right Catamaran

When you’re on the hunt for the perfect catamaran, the choices can be as vast as the ocean itself. From understanding the key differences between sail and power options to considering your unique sailing style and budget, we’ve got the guidelines to help you navigate this significant investment.

Sail vs. Power Catamaran

Sail catamarans are beloved for their elegance and eco-friendly operation. You’re harnessed to the wind, often yielding better performance and lower operating costs. Power catamarans, on the other hand, offer more consistent speeds regardless of wind conditions and typically feature more living space.

Considering Your Sailing Style

Whether you’re dreaming of leisurely coastal cruises or ambitious ocean crossings, your sailing style is crucial. For example, a sail catamaran with a deep draft improves windward performance for long voyages, while a power catamaran might be the ticket for weekend jaunts and entertaining.

Pros and Cons of Power Catamarans

Power catamarans excel in ease of handling and spaciousness. However, they typically have higher fuel costs, so consider this when comparing prices.

Size and Capacity

Determining boat size.

The size of your catamaran impacts everything from displacement to comfort. Larger models above 40 feet can offer 5 cabins, ample deck space, and enough storage for extended cruising. However, bigger boats also mean higher costs.

Passenger Capacity and Comfort

A catamaran’s design optimally balances capacity and comfort. Here’s a quick reference:

  • 2-3 cabins : Ideal for small families or couples.
  • 4 cabins : Good for larger groups or charter businesses.
  • 5+ cabins : Best for commercial use or those who entertain regularly.

Budget Considerations

Costs of catamarans.

The price of a new catamaran can range from a modest $200,000 to over a million dollars for luxury brands like Leopard Catamarans. Used models can bring significant savings, but factor in potential upgrade and maintenance costs.

Ongoing Expenses

Beyond the purchase price, be prepared for expenses such as docking fees, maintenance, insurance , and of course, fuel for power cats. The latter can significantly affect your budget, especially if you plan to log many nautical miles.

Finding the catamaran that suits your lifestyle, performance expectations, and budget is both an exciting and intensive process. Remember to weigh all factors carefully to ensure your final decision is one that brings endless days of joy on the water.

Maintenance and Care

catamarans5

Taking care of your catamaran not only keeps it looking great but also ensures it performs optimally for years to come. Regular maintenance can prevent costly repairs and extend the life of your boat. Let’s dive right into the nitty-gritty of keeping your cat pristine, shall we?

Essential Maintenance Tasks

“Prevention is better than cure,” they say, and it couldn’t be truer for your catamaran.

  • Hull Cleaning : It’s all about the smooth sail, isn’t it? Keep the hull free from marine growth with bi-annual clean-ups.
  • Electrical System: Battling corrosion is like facing the high winds at sea. Keep your electrical systems corrosion-free to prevent unexpected failures.

Maintenance Schedule

Sticking to a maintenance schedule is akin to following a treasure map – it leads you to the golden prize of a well-maintained vessel. For instance, oil should be changed at least every 150 hours of engine use.

  • Routine Check-Ups: Don’t forget to schedule these with the changing seasons, folks.
  • Professional Inspections: Sometimes, you need a seasoned pair of eyes. Yearly check-ups by a professional can spot issues you might miss.

Cleaning and Storage

A clean and well-stored catamaran means a ready-to-go boat when sailing season hits. Nobody likes a damp surprise onboard, right?

  • Dry Storage: Whenever possible, store your beloved cat on dry land.
  • Cover Up: Use a high-quality cover to shield from the elements – sun, rain, or residents of the nearby trees.

Cleaning Procedures for Catamarans

This is not just a splash-and-dash affair, my friends. Take heed of these steps:

  • Freshwater Rinse: After every outing, a freshwater rinse can do wonders against saltwater’s corrosive embrace.
  • Mild Soaps: Use gentle cleaners like Woolite or Dawn to keep that canvas looking dapper.

Off-Season Storage Tips

The off-season doesn’t mean rest for you. It’s prime time to ensure your catamaran rests well so it’s adventure-ready when you are.

  • Ventilation: Keep air circulating to thwart the ever-creeping mildew.
  • Battery Care: Don’t let your batteries go flat. Keep them charged and happy during the off-season.

From the yearly varnishing to the regular freshwater rinses, keeping your catamaran in sparkling condition is a rewarding journey. It’s not just about maintaining value; it’s about cherishing the vessel that carries you across the waters, creating memories one nautical mile at a time. So grab your maintenance kit and let’s keep those cats cruising!

Sailing Safety and Regulations

Ensuring your safety while enjoying the freedom of sailing on a catamaran involves understanding and adhering to essential safety practices and boating regulations. In this section, we’ll navigate through the crucial elements of safety onboard, understand the necessary equipment, and explore the legal requirements that keep you compliant and secure at sea.

Safety Equipment on Catamarans

Catamarans must be equipped with certain safety gear. It’s imperative that your vessel has life jackets for all passengers, fire extinguishers, visual distress signals, and other USA Coast Guard approved safety equipment. Have you checked your boat’s safety inventory recently?

Safety Guidelines for Catamaran Sailing

When you’re sailing a catamaran, it’s wise to “know before you go.” This means checking weather reports and understanding your boat’s limitations. For catamaran-specific tips, remember that while daggerboards or keels enhance performance, they should be handled with care, as they affect the vessel’s stability and maneuvering.

Boating Regulations

Did you know that boating regulations can vary by state and region? It’s not just about being legally compliant; understanding these regulations helps protect the marine environment and ensures that all boaters can enjoy shared waterways safely. Have a look at the U.S. Coast Guard Boating Safety regulations to stay updated.

Adhering to Maritime Laws

Finally, respecting maritime laws and customs is not only a legal obligation but also a mark of a responsible sailor. Here’s a compelling fact: strict adherence to maritime laws significantly reduces the risk of maritime accidents. So, keep abreast of navigation rules to ensure smooth sailing.

Remember, safety is the keel that keeps the exciting adventure of catamaran sailing stable and enjoyable – make sure it’s part of your voyage every time you cast off the lines. Now, are you ready to take the helm knowing you’re well-prepared for a safe journey?

FAQs (Frequently Asked Questions)

What are the advantages of sailing on a catamaran.

You’re in for a treat with catamarans — they’re like the luxury SUVs of the sea but without the fuel guzzling. Expect sheer stability, more living space, and less heeling than a monohull.

How Much Does a Catamaran Cost?

Thought about owning one of these beauties? Keep in mind, the sticker price varies wildly. We’re talking anywhere from $100,000 for a modest pre-owned vessel to north of a couple of million for a brand-spanking-new one, outfitted for luxury. Remember to factor in maintenance costs, which can set you back a few grand a year.

Are Catamarans Suitable for Family Vacations?

Absolutely, your clan will love the spacious decks and cabins that catamarans provide. It’s like a floating condo with the best ocean views.

What Safety Equipment Should I Have on Board a Catamaran?

Your catamaran should be your safe sanctuary on the seas. So gear up with life jackets, flares, VHF radios, and a dinghy for starts. Also, a solid first-aid kit and safety harnesses are invaluable.

David Ciccarelli

administrator

David Ciccarelli, is the Founder and CEO of Lake. He is based in Toronto, Canada, and is an expert in management, business administration, strategy, product development, and customer experience. His educational achievements include the Owner President Management Program at Harvard Business School (2019-2022) and the QuantumShift Program at Ivey Business School in 2017, aimed at CEOs of growing businesses.

Related Posts

Lake House Rentals with a Boat House

October 3, 2023

Lake House Rentals: Your Ultimate Getaway Guide for 2023

Icon

Lake houses are charming abodes that offer stunning waterfront views and bring a sense of ...

Boating on Lake Muskoka

Boating: Your 10-Step Guide to Driving a Boat Safely

Boating is a fantastic way to take advantage of the great outdoors and create unforgettabl...

Water Skiing

October 4, 2023

Water Skiing Essentials: Tips and Tricks for a Thrilling Experience

Water skiing is an exhilarating surface water sport where individuals ride on one or two s...

Don't have an account yet? Register

Already have an account? Sign In

Reset Password

Please enter your username or email address, you will receive a link to create a new password via email.

IMAGES

  1. Liveaboard catamaran plans

    catamaran hull plan

  2. Optimising Hull Lines for Performance

    catamaran hull plan

  3. Free Beach Catamaran Hull Plans

    catamaran hull plan

  4. Mystic Offshore C5000 Catamaran Dimensions Page 2 of 4

    catamaran hull plan

  5. How Build Catamaran Plans Free Download

    catamaran hull plan

  6. Proa File

    catamaran hull plan

VIDEO

  1. boat builders dream custom catamaran biuld 47ft luxury #boatbuilding #catamaran #powercat #boating

  2. GENERATING CATAMARAN HULL USING MAXSURF MODELER

  3. RC boat Catamaran Zenoah V2 twin (66 mph)

  4. Luxury catamaran

  5. Trimarans are an interesting hull design for sure #boat #powerboat #fishing

  6. Classic yachts and performance catamarans; the beauty of boats #catamarans #catamaran #boatsforsale

COMMENTS

  1. DIY Cruising Catamaran: Complete Building Guide

    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.

  2. Catamaran Hull Design

    The most important catamaran design hull shape factor, is the Prismatic Coefficient (Cp). This is a measure of the fullness of the ends of the hull. Instinctively you might think that fine ends would be faster as they would "cut through the water better". But in fact you want a high Cp for high speeds.

  3. Catamaran and Trimaran Boat Plans

    However with all things considered, building a multi can be an amazing journey. Fast Twin Catermaran. $ 30.00 - $ 45.00 (USD) Lively 28 Cruising Trimaran. $ 170.00 - $ 185.00 (USD) Lively 35 Cruising Trimaran. $ 355.00 - $ 370.00 (USD) Catamaran & Trimaran Boat Plans from Hartley Boats make it a reality to build your own multihull at home.

  4. Catamaran Construction

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

  5. Plans For Catamarans And Monohulls

    YACHT DESIGN. We provide stock boat plans for both monohull and multihull sailing vessels, including sailing skiffs and sharpies. Our designs mainly feature timber construction, in plywood or cedar strip plank composite construction, using the W.E.S.T. system (wood epoxy saturation technique). Our designs are intended mainly as cruising boats ...

  6. Kurt Hughes Multihull Design

    My new blog: MultihullBlog.com. 3123 Fairview Ave E. Seattle, WA 98102. Order the Latest Design Portfolio today to see over 85 multihull plans in stock. Besides illustrating my stock designs, for which I sell study plans and full construction plans, it also contains my design philosophy of multihulls; an article on the rapid Cylinder Mold (pdf ...

  7. Catamaran Stock Plans

    Catamaran Stock Plans. ... Plans are leased to build ONE boat, NO time limit. Tri-Star designs are proven designs, sailing the seven seas since 1964. Free consultation is provided to the original non-professional builder till he or she is sailing the seven seas. All boats may be built with flared hulls, with the exception of the TRI 25, TRI ...

  8. Catamaran Construction with a DuFlex Kit

    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.

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

    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 ...

  10. 15' Coastal Power Cat

    Plans for this Coastal Power Cat include the following sheets. 15' Plywood " Flat Cat". Tunnel hull. Center console. L.O.A 15'-6" x Beam 6'-11´x Draft 10" 4.72M. 2.11M. ... The hull is a "false" catamaran with a tunnel that's partially immersed. A built-in "venturi" minimizes the wetted surface once the Flat Cat gets up ...

  11. Our Catamaran Build Kits

    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. ... 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 ...

  12. Bruce Roberts, CATAMARAN boat plans, CATAMARAN boat building

    POWER CATAMARAN PLANS and KITS, CATAMARAN PLANS , Bruce Roberts WEB SITE offers catamaran boat plans and catamaran boat kits for fiberglasss and aluminum boat designs, cut to size CATAMARAN kits, part built boats or complete boats. Bruce Roberts Yacht Designs offer boat building project management arrangements for boats built overseas at affordable prices.

  13. Catamaran Design Guide

    By instinct we will know that a catamaran with a wide stance and a conservative sail plan will be very stable offshore. The SC formula will inevitably illustrate that a wider beamed catamaran with a tall sail plan will be as resistant to wind induced capsize as a short-rigged, narrower boat. ... No, the hull floor of a catamaran is not always ...

  14. Catamaran Design Formulas

    T c = 0.57. Here we put B TR = 1.9 to minimize boat resistance (for her size) and get the draft calculation for a canoe body T c (Figure 1). Midship coefficient - C m. C m = A m / T c (x) B WL. We need to estimate a few coefficients of the canoe body. where A m is the maximum cross section area of the hull (Figure 3).

  15. Trimaran Plans

    The DESIGNER'S book TRIMARAN and CATAMARAN CONSTRUCTION is part of the plans (over 21') and covers all phases of construction. Plans are leased to build ONE boat, NO time limit. Tri-Star designs are proven designs, sailing the seven seas since 1964. Free consultation is provided to the original non-professional builder till he or she is sailing ...

  16. Mike Waller Yacht Design

    CC40 CATAMARAN. This ocean voyaging cat is in multi-chine plywood, and has two seperate hulls, a center cockpit with cuddy, and unbelievable accomodation for a vessel of this type and size. Mike Waller Yacht Design provides comprehensive plans for amateur boat builders. A range of stock plans are available for both monohulls and multihulls ...

  17. Open Source 13-15m Catamaran Plans

    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 ...

  18. Design Dynamics

    Design Dynamics. Amultihull, just as any other type of boat, presents a series of compromises, and this applies to overall hull, deck and configuration as well. Concessions often have to be made because of space, performance or construction costs. In addition, the intended usage will be a significant factor in determining the shape and size of ...

  19. Catamaran Hulls- Everything You Need To Know

    Hulls are what sets this boat apart from the rest. The catamaran has two hulls, while the monohull, as the name suggests, has only one hull. Most of the advantages of this boat are hinged on these two hulls. The bridge deck connects the two catamaran hulls. On top of the catamaran hulls and the bridge deck is the deck.

  20. Optimising Hull Lines for Performance

    A discussion about catamaran hull shapes and how they relate to performance and sea keeping with specific reference to the 33' catamaran Mad Max. ... This is the rocker line isolated from the lines plan above (in blue) and and the red line shows a more moderate rocker line that achieves the same buoyancy and maintains the centre of buoyancy in ...

  21. 35 FT Catamaran Workboat (616)

    35 FT Catamaran Workboat (616) This design (plan) is a 35 FT aluminum catamaran. Power is two (2) Volvo D4-225 DP I/O at 189 HP each. Gross weight and speed dependent on final arrangement. *The above price is for the construction plans and a onetime use of the CAD cutting files.

  22. Catamarans Uncovered: Ultimate Dual-Hulled Sailing Guide

    The dual-hull design of catamarans allows for a wider beam, which translates into more deck space. When compared to monohulls, ... The latter can significantly affect your budget, especially if you plan to log many nautical miles. Finding the catamaran that suits your lifestyle, performance expectations, and budget is both an exciting and ...

  23. PDF Displacement Power Catamarans

    The power needed to do 30 knots is about (2) 450 hp or 900 hp. One live example of a displacement catamaran is the HoloHolo on Kauai. See www.holoholocharters.com Its 62' long, weighs about 25,000 lbs, has a pair of 440 hp engines and operates in some of the most severe waters in the US.