diy power catamaran

DIY Cruising Catamaran: Complete Building Guide

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

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

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

Why You Might Want To Build Your Own Catamaran

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

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

Knowing Your Boat

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

Pride of Ownership

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

Substantial Cost Savings

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

Freedom To Create Your Own Designs

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

Great Learning Experience

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

What To Look For in Catamaran Boat Designs

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

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

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

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

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

How Much Would It Cost To Build Your Own Catamaran?

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

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

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

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

What You Will Need

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

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

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

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

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

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

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

How To Build a Catamaran

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

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

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

Prepare the Essentials

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

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

Build the Mast Beam

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

Build the Boat Hull

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

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

Sheathe the Hull

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

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

Install the Bulkheads

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

Construct the Interior Structure

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

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

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

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

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

Launch Your Cruising Catamaran

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

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

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

The Pros of Building a Catamaran

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

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

The Cons of Building a Catamaran

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

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

DIY Cruising Catamaran Tips and Tricks

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

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

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

Final Thoughts

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

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

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

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

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

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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..

diy power catamaran

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!

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ECO 75 Power Cat Plans

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ECO 75 Power Cat Plans

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Description

Additional information.

The ECO 75 power cat is the big brother of the ECO power cat. Designed along the same lines and with the same philosophy. Easy to build boat by an amateur. Construction is the time proven plywood/glass fiber/Epoxy composite system. Nothing can match this system for weight, costs and easy of construction. Besides this advantages no maintenance will be necessary over many years.

The hulls start with a deep V on the bow and a wide V at the transom. So the boat will be sea worthy. The hulls are designed for medium speed. Speed with a 25 HP engine will be around 25 knots full power and 18 knots at half power. So the boat will be very ECOnomical to run and maintain.

One attractive features is the front cockpit. This is not only a nice place for sun bathing but also a safe place for anchor maneuvers. The front hatch makes it not necessary to walk over the deck in a bad weather situation.

diy power catamaran

1 Forward cockpit6 locker11 berth
2 Anchor7 pantry12 settee/double berth
3 bench8 steering position13 bath room
4 entrance to cockpit9 cockpit lockers14 hanging locker
5 steps10 cockpit15 steps

The inside lay out with the enclosed bath room speaks for it self. In hulls have standing height. The height on the bridge deck saloon is 1,20m. Enough for comfortable seating on the settee. The boat is build from 8 and 6mm plywood over stringers. The construction manual describes an easy way for fairing. In the end this is the quickest way to build the boat. The whole boat is covered with fiber glass and painted with PU paint.

The plans consists of 20 drawings. The technical drawings are to scale 1 : 1. File format PDF (DXF files available. The 14 pages manual gives a description of the construction of the boat.

Click HERE for a sample drawing

L.o.a.-7.50 m
Beam-3.22 m
Weight empty-800 kg
Weight max. CWL-1400 kg
Outboard engine-20-40 hp
Speed-18-25 knots

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Skoota 24 Power Cat Plans Download

Skoota 24 Power Cat Plans Download







The designs where there is a YELLOW BACKGROUND are the designs for which CUTTING FILES are available.

 

 

 

 

 

  

 

"It is great that with 164 HP twins I can now get 30 knots out of her" 

 

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6-465-470

 

 

 


 


 

 

 

 

 

 

  Boat is well up to expectations. Have experienced some heavy weather and are impressed by the stable ride especially to windward. Judy can still use the vacuum cleaner at 30 knots +  She is alo impressed by her washing machine and dishwasher not to mention the deep freeze !!  Large Rig but easily handled by 2 persons.

 

 

 

 

 

 

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The Spirited 400 'Power' is a semi-displacement power cat with sleek lines and light weight structure. For those who like 'turn-key' cruising this highly efficient design is always in readiness for a quick getaway. The slim hulls run easily through the water and provide a very comfortable ride even in rough conditions. This design can accommodate most luxury appointments for an apartment-like finish and experience. 

Cockpit The acess into the cockpit is via the aft hull steps with the bottom step being extra long and in effect acting as a duckboard ideal for entering/exiting the water when swimming, diving or unloading the tender. The cockpit is open plan with a wide curved seat aft and additional seating either side. The open plans layout offers the option of a clear area or space to set up a table and chairs when required.

Bridgedeck Internally this design has the galley to Starboard against the aft bulkhead; opposite this is a generous sized seating area. The bridgedeck cabin is high volume and accommodates a dedicated steering console area with comfortable seat and dashboard design. This space works cohesively between all areas and provides a hub for the living areas while underway or at rest.

Cabins Entering the hulls there are three private double cabins, the two forward are queen sized and have the option of an ensuite or a walk-in-robe leading forward. All areas are spacious enough for comfortable use with all berths allowing for generous sitting headroom. Head and shower amenities are situated aft in the Port hull with a dedicated engine bay behind the separate shower; the Starboard engine is located below the aft double berth.

Power The engine size is flexible due to the semi-displacement hull design which is efficient at any speed range. The recommended engine size begins at 50hp through to a maximum of 125hp in a shaft-drive installation.

On Deck The surfaces are flat and level for safe clutter-free footing from the cockpit moving forward to the foredeck. The foredeck flows seamlessly onto the trampolines and also level with the forebeam. Access to the flybridge is from the cockpit on the Starboard side. The flybridge is the perfect outdoor social setting with excellent 'birds-eye' vision of the horizon. An optional second top steering station can be fitted for full control whist enjoying this area and is also advantageous when docking from this position. 

Performance Expected speeds depend on engine size but cruise speeds will be effortless in the mid teens even with the smaller engines. Top speeds are in the high twenties with the large engines and in the high teens with the smaller sized engines. Given the fine entry hull design this design will cut through the water and offer a comfortable level ride in most conditions. 

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Construction plans only

The plans can be purchased separately and the materials can be sourced by the client at their own pace. A  list of the required and recommended materials is provided.

Cad-drawn colour construction plans are supplied in an A3 sized booklet of high detail specifically suited to amateur building.

Study Plans

Study Plans are available for this design, please send a request via our  Contact  page.

How to Order your Spirited 400?

Purchase Order Please complete the online contact form.  Online Form

Order Confirmation On receipt of your order form we will provide you with an order confirmation with the costs and deposit requirements. 

Payment Generally a deposit is made at order and a final payment is made prior to dispatch. Payment for the larger design range is generally made via direct deposit and these bank details are provided on your order confirmation. Payments are made in Australian dollars.

Delivery Estimated delivery times is provided on the Order confirmation. We will contact you with a delivery date and delivery options once the kit has been ordered.

Contruction Plans Printed to order with customised cover sheets and any other design requirements to meets the clients requests.

Kits Pre-cut to order as standard or to meet any specific customised requirements.

Components Built to order as standard or to meet any specific customised requirements.

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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.

diy power catamaran

Fast Twin Catermaran

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Lively 28 Cruising Trimaran

diy power catamaran

Lively 35 Cruising Trimaran

 

Ed Horstman designed TRIMARAN and CATAMARAN plans are drawn for the first time builder. Plans are concise and clearly drawn so the builder can easily follow each building step. Designs are continuously updated with your input and new ideas. Plans include full size patterns to 63'. The larger TRI's and CAT's have full radius hulls.With no lofting you build right away. 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 the seven seas. All boats may be built with flared hulls, with the exception of the TRI 25, TRI 26MT, CAT 27PC and the CAT 27. A DESIGN FEE for customer modifications to stock plans.

Small, Fast Catamaran Design


TRI-STAR CAT 14 Plans $ Slightly Larger, Fast Catamaran Design




TRI-STAR CAT 19 Plans $ Trailerable, Fast Catamaran Design with berthing areas



TRI-STAR CAT 27 PC Study Plans $
TRI-STAR CAT 27 PC Plans $

A comfortable micro-cruising catamaran.



TRI-STAR CAT 27 Study Plans $
TRI-STAR CAT 27 Plans $

CAT 34, designed as a mid-size comfortable, quick sailing catamaran with comfortable accomodations, a spacious bridge deck lounge area that has 6ft of headroom.


TRI-STAR CAT 34 Plans $ CAT 36 designed as a spacious, fast enjoyable sailing cataramarn with accomodations found only on much larger yachts.

TRI-STAR CAT 36 Study Plans $
TRI-STAR CAT 36 Plans $

CAT 38 designed as a spacious, fast enjoyable sailing cataramarn with accomodations found only on much larger yachts.

TRI-STAR CAT 38 Study Plans $
TRI-STAR CAT 38 Plans $

CAT 41 designed as a spacious, fast enjoyable sailing cataramarn with accomodations found only on much larger yachts.

TRI-STAR CAT 41 Study Plans $
TRI-STAR CAT 41 Plans $

CAT 51 is an elegant cruising or charter catamaran, designed for the owner desiring a spacious, enjoyable sailing catamaran.

TRI-STAR CAT 51 Study Plans $
TRI-STAR CAT 51 Plans $

CAT 55 is an elegant cruising or charter catamaran, designed for the owner desiring a spacious, enjoyable sailing catamaran.



TRI-STAR CAT 55 Study Plans $
TRI-STAR CAT 55 Plans $

 

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

Duflex Kit Construction Step.1

Step 1. Kit Design

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

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

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

Duflex kit construction Kit image-01

Step 2. Unpacking

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

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

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

Duflex Kit Construction Step 2 image-02

Step 3 Joining the Panels

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

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

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

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

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

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

Duflex kit construction Step 3 image-01

Joining the panels with  clamping pressure

diy power catamaran

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

Joining the panels with the Z Press

diy power catamaran

Step 4 Stacking Joined Panels

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

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

Diuflex Kit Construction Header image step 5.

Step 5. Separating the Parts

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

Duflex kit Construction Step 5 Image-01

Step 6. ASSEMBLY

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

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

Duflex Kit Construction Assembly image-01

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

Duflex Kit Construction Header Image Step 7

Step 7. Interior

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

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

Duflex Kit Construction Step 7 Image 2

Step 8 Fairing, Painting, Hardware Installation

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

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

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

Duflex Kit Construction Step 8 Image 2

Step 9. Sailing

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

diy power catamaran

DuFLEX Kits are manufactured and supplied world wide by ATL Composites

atlcomposites.com.au

And in Europe by VDL Composites

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

For more information on DuFLEX and associated Products 

atlcomposites.com.au/category/27/DuFLEX

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Power Catamarans: A Complete Guide

Dec 06, 2023

less than a min

Power Catamarans: A Complete Guide

Power Catamarans, often termed as the epitome of modern maritime engineering, are gaining popularity for all the right reasons. Their distinct design, enhanced stability, and cruising efficiency set them apart from traditional monohull boats and even their sail-driven counterparts. This guide dives into the world of Power Catamarans, shedding light on their advantages and how they compare to other vessels like monohulls and trimarans.

Historical Prelude:

The concept of catamarans traces its roots back to ancient maritime cultures. However, the power catamaran is a relatively modern innovation that marries the traditional twin-hull design with powerful engines, offering a unique blend of speed, stability, and space.

Distinguishing Design:

Power Catamarans are characterized by their twin hulls, which significantly reduce the drag, thus enhancing speed and fuel efficiency. Unlike monohulls, they have a broader beam, which contributes to increased stability and more living space. The absence of a ballast for stability further lightens the vessel, contributing to its speed and fuel economy

Speed and Handling:

One of the significant advantages of power catamarans is their speed and handling. The twin hulls allow for a smoother glide over the water, making them particularly favorable for watersports enthusiasts. Their handling in rough waters is superior to monohulls, thanks to the inherent stability provided by the dual-hull design.

The stability of power catamarans is unparalleled, especially when compared to monohulls. The wide beam and twin hulls provide a stable platform, reducing the rocking and rolling common in monohulls. This stability is not only comforting in rough seas but also crucial when docking or anchoring.

Comfort and Space:

The spacious design of power catamarans offers homelike livability, with ample room for cabins, lounges, and even onboard amenities like grills and bars. The wide beam also allows for large deck spaces, ideal for sunbathing or enjoying the scenic ocean vistas.

Economy and Redundancy:

Power catamarans are economical, with fuel efficiency being one of their selling points. The redundancy built into their design, with separate engines for each hull, provides an added layer of safety, ensuring that the vessel can return to shore even if one engine fails.

Regular Upkeep and Care:

Power catamarans, given their unique design and structure, come with their own set of maintenance requirements. Like all boats, routine checks and upkeep are essential to ensure smooth sailing. The twin hull design means double the underwater gear – from propellers to rudders, which necessitates regular inspections for any signs of wear, tear, or fouling.

Antifouling:

Given that power catamarans have a larger surface area underwater due to their twin hulls, they may be more susceptible to marine growth. Regular antifouling treatments can help in keeping the hulls clean, ensuring optimal performance and fuel efficiency.

Engine Maintenance:

One distinct advantage of power catamarans is their dual-engine setup, but this also means double the engine maintenance. Regular oil changes, cooling system checks, and filter replacements are crucial. It's beneficial to synchronize maintenance schedules for both engines to ensure consistent performance.

The lifespan of a power catamaran largely depends on its build quality, materials used, and how well it's maintained. With proper care, a power catamaran can last for several decades. The engine's maintenance significantly impacts the catamaran's lifespan, with gasoline engines requiring maintenance at 1,200 to 1,800 hours and diesel engines at around 5,000 hours​​. The construction materials play a crucial role; for instance, fiberglass catamarans, when well-maintained, can last for many decades, while aluminum cats might change ownership after 10-15 years but can last a lifetime with proper care​.

World-Renowned Builders:

The power catamaran sector boasts several reputable manufacturers such as Lagoon, Leopard Catamarans, Fountaine Pajot, and other notable names like Seawind Catamarans​.

Lagoon, a revered name under the Beneteau Group umbrella, has carved its niche in crafting luxurious, spacious catamarans. A prime example is the Lagoon 630 Motor Yacht, embodying opulence with its nearly 250 sq. ft. aft deck and 900 sq. ft. interior, comfortably housing up to 12 guests. Known for its superyacht styling, it boasts superior fuel efficiency and a commendable average velocity-made-good of 9 knots.

Leopard Catamarans:

Emerging from the reputable Robertson and Caine shipyard in South Africa, Leopard Catamarans is synonymous with innovation and efficiency. The Leopard 53 Powercat is a testament to this legacy, showcasing excellent seakeeping abilities, offering 3 or 4 cabin configurations, and achieving a top speed of 25 knots.

Fountaine Pajot:

A trailblazer since 1976, Fountaine Pajot constantly redefines catamaran design. The Fountaine Pajot MY6 is a shining example, encapsulating the brand's visionary ethos. Stretching 15 meters, the MY6, equipped with dual engines of up to 2 x 353 Kw and 2 x 480 hp, promises dynamic sailing. Crafted meticulously by Pier Angelo Andreani, the interior mirrors a 20-meter monohull's spaciousness, reflecting modern aesthetics and comfort that stand as a benchmark in the Motor Yacht world.

These manufacturers continue to innovate, offering a blend of luxury, performance, and efficiency in their power catamaran models, making them a popular choice among maritime enthusiasts.

Comparing with Monohulls and Trimarans:

While monohulls are traditional and often cheaper, they lack the stability and space offered by power catamarans. On the other hand, trimarans, with three hulls, provide even more stability but at the cost of additional drag and less interior space.

TheBoatDB - Your Gateway to Maritime Exploration:

If you’re looking to delve deeper into the world of power catamarans and other vessels, TheBoatDB offers a comprehensive boat database. Explore various catamaran models, compare them with monohulls, trimarans, and other types of boats, and make an informed decision on your next maritime adventure.

In summary, power catamarans encapsulate a modern engineering marvel in the maritime domain. Their blend of speed, stability, comfort, and economy makes them an attractive option for a broad spectrum of boaters. Whether you are a long-distance cruiser, a water sport enthusiast, or someone who cherishes the tranquility of the sea, a power catamaran could be the vessel that transforms your maritime adventures into unforgettable experiences.

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Sail And Power Catamarans: Developing A 'Catitude'

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Once you get the hang of it, multihulls are a blast to drive. Here's how to handle these versatile, comfortable boats — sail or power — for those considering chartering a cat.

A 43-foot catamaran with a man standing on the bow holding onto the mainsail as the catamaran cruises through the blue water

This 43-foot cat is trimmed well for upwind sailing. But once main and boom are eased out to accommodate wind direction, the jib may create a pinched slot as jib tracks are located on cabin tops. (Photo: Privilège Catamarans/Nico Krauss)

As a freelance marine journalist with a U.S. Coast Guard 100-Ton Master license, I get to captain dozens of boats of various designs and sizes. I'm also a cat convert from monohull boating with plenty of firsthand knowledge to share. If you're thinking of chartering or buying a cat, you'll benefit from their inherent advantages. Cats offer more room than the same-lengthmonohulls, they usually have better system access, and sailing cats may be faster in light wind because they're not dragging a heavy keel through the water.

Cats operate upright so you won't be on your ear in a blow. You can cook and sleep on a passage without "walking on the hull" like in a monohull that's heeling. You also spend more time above the waterline on a cat rather than the dreaded "down below" on a monohull.

Of course, for all the pluses, there are minuses: Finding a marina berth for a cat is difficult and expensive. Unlike monohulls that get into the groove and slice through waves when sailing upwind, cats can slap the water if the bridge deck clearance is low, or when the seas meet the underside of the bridge deck.

People who usually sail monohulls may be accustomed to being alerted to the wind rising too much by the increasing heel of the boat. If you get this amount of heeling in a cat, you may be beyond the point of no return; though this isn't as likely with many of today's heavier, wider models. Cats are not self-righting; you have to stay alert to worsening weather.

Also, unless it's a performance model with daggerboards, a cat only has mini-keels, so it won't point high and can be a bit like maneuvering a shoebox. They don't track well, tending to slip to leeward, and they tack slowly because they have to push two hulls rather than one through the eye of the wind. Finally, cats have fairly shallow rudders, so close-quarters maneuvering comes more from dual engine thrust, rather than the water flowing over the rudders — effective, but something to get used to.

Adjustment to the position of the jib to improve wind slot performance illustration

An easy adjustment to position the jib out farther and improve performance is shown in this illustration.

When it comes to the emerging power-catamaran trend, driving cats under power is a straight-up joy. Their two props are set wide apart resulting in much better control and precise maneuvering in close quarters. Cats don't coast like monohulls because they don't have a keel to keep them tracking, so gliding into a dock at a shallow angle doesn't work, and neither does using propwalk to tuck in the stern. You use the engines to spin a cat in its own length or walk it sideways, both of which are easier to master than the nuances of driving a monohull.

Regardless of whether you're docking, picking up a mooring, or anchoring, always keep the boat powered up and ready to drive until you're done because you can't just push a 45-foot cat around by hand. Here are some handling tips that apply to handling both sail and power catamarans.

Don't Ding The Dock

When there's no wind, bigger sailcats also have an engine, which is needed in each hull. They aren't powered to drive as fast, but the principles are the same. Keep in mind, boats and conditions are varied, so we can only give examples here.

  • Forget about the wheel when docking side-to or forward. Lock it on the centerline with the wheel lock or by leaning your body against it and maneuver using the throttles (see illustrations below). Power forward with the starboard engine, and aft with the port, and the cat moves to port and vice versa. Turn this around in your head when in reverse. Fine tune adjustments by using one engine at a time. Pause the propeller in neutral when changing directions from forward to reverse and vice-versa to give transmissions time to engage.

Walking a catamaran sideways to dock port and stern illustration

  • Backing into a slip: Cats dock stern-to because the bows are high and it's easier to step on and off the dock via the swim platforms aft. When backing straight into a slip, come abeam, pivot 90 degrees with the engines until centered, and back in. If Med-mooring, drop anchor and pay out the rode slowly as you back with both engines. Set the anchor part way back, then keep backing and letting out rode until you're close enough to the dock to tie up the stern lines. Have fenders already tied aft to cushion the transoms. Tighten up on the anchor rode with the windlass.

Wind And Current

As with any boat, it's best to work against the current for better control.

  • When departing a starboard tie-up with the current coming at the bow, put a fender and line on the starboard aft corner, power aft with the port engine, pivot, then drive out forward with both engines against the current. If the current is coming from behind, back out, putting a line and fender on the starboard bow. Power in reverse with the starboard engine, pivot, and then back out with both engines.
  • Cats have high cabin tops, producing lots of windage. In tight quarters, you may need to turn more sharply when approaching a dock or line up to windward before backing in.

Picking Up A Mooring

Cats have high hulls and it's easy for the skipper to lose sight of a mooring ball before the boat is close enough for the crew to pick it up. Keep the mooring on the side where you can best see forward so you can keep an eye on the ball at all times. (Some cat helm stations are offset to one side or the other.)

  • Hand signals or a headset for you and the crew make communications easier to send and receive rather than yelling.
  • Have your crew pick up the mooring with a boat hook while you maneuver with the engines to keep station — easier on a cat than a monohulls, even in wind and current.
  • Have lines ready by stringing one off a cleat on each hull. To do this, thread each line through the eye or loop, then back onto its cleat. Do this with both sides and adjust until the mooring sits on the centerline. This will minimize swinging and chafe, and noise in the forward cabins.

Anchoring is generally easier on a cat than a monohull. There's more room forward for crew to work, and you can keep the boat steady with the engines.

  • A bridle should be preset with a line from each hull (under the trampoline) and hook or shackle in the middle. Once the anchor and chain is down, attach the bridle to the chain (usually done near the windlass) and set the hook putting the pressure on the bridle. Once set, let out enough chain to create a catenary.
  • When raising anchor, take care to keep the chain in between the bows or you risk damaging the fiberglass by shaving the bottom of one or the other if you overrun the chain or lose track of where it is. Crew communication is critical.

Sail-Specific Cats

Here's how to coax the best out of a sailing catamaran:

  • Big cats carry huge mainsails, so raising one typically requires an electric winch. It also may be challenging to keep full battens out of the lazyjacks that hold up the sail bag, so it can take a few people to raise a large sail. Also, there are usually multiple angles to the way halyards are run on cats with flybridges, resulting in friction. So "dropping" the mainsail can be more like "pulling" it down. Attach a messenger-type line to the mainsail head so it comes down easier.
  • Reefing can be a guessing game because you don't feel a cat being overpowered like you do a monohull. Depending on the direction of sail and the sea state, you may be able to reef a little later with the wind a few knots higher — an individual call.
  • Cat headsail tracks are typically on the cabin top making the sail curve back on itself, creating a wind break when it's sheeted in. A trick is to bring a spare line from the jib clue out to a cleat on the side deck to open up the slot to let air flow through. Check for chafe on the cabin and don't forget to release it before tacking.
  • The majority of multihulls are built to sail on a beam or broad reach, and that's where they're the happiest. Dead downwind, cats shimmy a little making wing-on-wing sailing tricky, not all that different from monohulls. For more comfort, choose one broad reach or the other, then jibe when necessary.
  • Cats with daggerboards can point higher and track better because, like monohulls, they have an appendage (or two) down low in the water for a better center of lateral resistance. Daggerboards are mostly used when sailing upwind, and it helps to keep the leeward board lower than the windward one. Sailing downwind with the boards lowered could create a tripping hazard, especially in rough seas where it's possible to stuff the bows into the wave ahead. When motorsailing, a trick to saving fuel and pointing higher is to run only the leeward engine for a little pointing assist.

Next time you have an opportunity to test drive a power or sailing cat, or to charter one on your next holiday, try it! The learning curve is so quick, it's really fun, and before you know it, you, too, may convert to being a cat person!

Catamaran Brands

You can further explore the array of catamarans, big and small, power and sail, by visiting any of these leading manufacturers.

  • Aquila Power Catamarans
  • Aspen Power Catamarans
  • Fountaine-Pajot
  • Horizon Power Catamarans
  • Leopard Catamarans
  • Nautitech 47 Power
  • Balance Catamarans
  • Fountaine Pajot
  • Outremer Catamarans
  • Seawind Catamarans

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  • Paddle Board

Boating Beast

A Guide to Power Catamaran Boats

John Sampson

If you’re into offshore fishing or water sports, the Power Catamaran or “multi-hull powerboat” offers you a great option for your first vessel. These powerboats provide you an excellent combination of performance, stability, and maneuverability.

These boats have a catamaran design, relying on two hulls to float the vessel instead of the typical deep-V hull found on other powerboat models. The multi-hull powerboat is ideal for cruising, and you can set it up for fishing or watersports as well.

With the multi-hull powerboat, you get options for multiple fishing stations over each hull without disrupting the boat’s balance on the water. They are ideal for use in lakes and estuaries, and they excel on the open ocean.

These boats come in lengths ranging from 16 to 30-feet, with plenty of customizable options and accessories. Typically, you get a stern-drive or outboard motor configuration, with center consoles for the driver and loads of storage space onboard.

These boats can carry from six to eight passengers easily, and most models will fit on trailers. This post gives you all the information you need on selecting the right multi-hull powerboat to suit your aquatic needs.

What Is a Multi-Hull Powerboat?

The multi-hull powerboat features a catamaran design, with two hulls running down the boat’s length, featuring a gap between the two. This configuration makes the boat exceptionally stable at higher speeds, allowing fast movement through choppy water inshore or offshore.

The catamaran might seem like a niche boat design. However, it offers you several advantages on the water, such as a smooth ride, stability, and economy. These boats come in a wide range of designs and lengths, with the smallest versions measuring around 12-feet, and the largest extending up to 70-feet or longer.

The longer vessels come with liveaboard facilities and all the amenities you need to spend days out on the water. We like to think of the multi-hull powerboat as the catamaran design of the cabin cruiser or cuddy cabin boat. You get all the same advantages as these models but with an added performance on the water.

Multi-Hull Powerboat

You get plenty of options for live wells, rod holders, gear storage, and integrated coolers for drinks and fish. Whether you’re planning a weekend trip or just going out for the day, the multi-hull powerboat is a great choice for your ocean-going excursion.

While the catamaran model is the most popular choice in this category, there are models featuring a tri-hull design. Typically, these vessels cater more towards fishing than performance or watersports, offering slightly less steering maneuverability than the dual hull setup. However, the addition of the third hull brings superior stability to the boat, making them ideal for fishing in choppy water or cruising from island to island on rougher seas.

The ripple hull models typically feature more liveaboard space, with some models having multiple separate living areas beneath the deck.

Benefits of Multi-Hull Powerboats

The Multi-hull powerboat offers you plenty of advantages for fishing, cruising, and watersports. Here are our top reasons for adding this boat to your shortlist of considerations.

Speed and Handling

The multi-hull boat relies on two separate hulls contacting the water. As a result, there is less drag from the hull when cutting through the water. You get faster speeds than you do with a mono-hull design and excellent handling with tight turning circles. These boats do well on open water, allowing for superior stability in rough waters when fishing offshore.

Dynamic Cruising

The multi-hull powerboat features dynamic cruising capability. These boats are most popular with recreational users that want to cruise down the coastline on the weekend or take a few days out on the water for a fishing trip. The built-in accommodations in many designs make it suitable for staying out on the water overnight.

Stability and Performance

Multi-hull powerboats can come with several engine configurations. The motors on these boats offer excellent performance, propelling the watercraft up to speeds of 50 to 80-mph, depending on the model. They also make suitable watersports boats, allowing for skiing and wakeboarding.

Plenty of Storage

The multi-hull boat offers you more storage capability than mono-hull models. You get loads of storage room above and below deck for your dive gear or fishing equipment. There is under-seat storage, and the v-berths in the bow of these models can include plenty of amenities.

Cabin of the Calcutta 480 Catamaran

Center Console Design

The center console driver configuration is common with the multi-hull performance boat. This driver position gives you more control over the vessel when turning. Some consoles may position closer to the bow or aft of the boat, depending on the length and design features of the boat.

Hardtop Designs

Most multi-hull powerboats come equipped for long ocean-going trips. As a result, they may have a covered driver cockpit leading to below deck accommodations or storage facilities. Some models have wraparound cockpits with doors sealing the cabin, allowing for air conditioning inside the boat on hot days. Other models come with an open plan design and a hard roof.

Trailerable

Most models of multi-hull power bats range from 16 to 24-feet, but there are plenty of longer models. The shorter lengths are easy to trailer, allowing for easy removal for the water and transportation. However, some models may be wider than 10-feet, requiring a special license to operate the loaded trailer. Check with your local authorities for trailer regulations and laws.

Fishing and Watersports Capability

These boats are excellent fishing vessels, offering you plenty of stability for casting on any side of the boat. The center console design means you have walkways on either side of the console, allowing the angler to chase the fish around the boat if it decides to drag the line. Most models also feature setups for watersports like wakeboarding, with T-tower bars or Bimini tops for higher tow points.

Outboard or Stern Motors

The multi-hull powerboat comes with a design for performance out on the water. As a result, these boats usually feature outboard motors with capacities ranging from 150-HP to 450-HP. Some models may use dual-motor setups or stern-mounted motors that hide out of sight.

Multiple Sizing Options

As mentioned, the multi-hull boat comes in a variety of lengths to suit your requirements. Whether you need a large boat for spending days out on the water or a simple day fishing vessel, there’s a multi-hull design to suit your requirements.

Disadvantages of Multi-Hull Powerboats

While the multi-hull powerboat is a flexible design suited for cruising, fishing, or water sports, it does come with a few drawbacks.

Large Engines and More Fuel

These boats feature design and construction for speed, with large outboard motors. As a result, they are somewhat heavy on fuel, especially with a large-capacity dual-motor setup.

Top Multi-Hull Powerboat Models

You have plenty of choices when selecting your multi-hull powerboat. Here are some of our top picks for the best models available.

Calcutta 480

This multi-hull powerboat has a 51-foot length, and it’s ideal for offshore use, providing exceptional stability thanks to the size and the 17-foot beam. It’s one of the largest models available, featuring world-class multi-hull design.

You get a spacious deck with a center console configuration and enough room to walk down either side of the boat when fishing. The dual hull provides exceptional stability combined with the long length, and you get options for diesel-powered or gasoline engines in outboard or in-stern setup to suit your requirements.

Calcutta 480

The Calcutta brand custom-builds boats for its clients. You get options for fully enclosed bow areas and fishing-style cabins with a roomy helm deck and a sleeping berth included in the bow. You also have an enclosed head for ablutions, but there is no option for a shower.

This model comes with an enclosed cockpit and air conditioning to keep you cool when cruising. The motors on this boat are monsters, featuring a twin setup of 550-HP Cummins diesel inboards available on the sports version for superior power and speed on the water while maintaining the boat’s maneuverability.

There’s a 600-gallon fuel capacity for the thirsty engines, allowing you to spend days out on the water without running out of fuel.

Insetta 35 IFC Hydrofoil

The Insetta 35 IFC hydrofoil offers you the smooth-sailing benefit of hydrofoils, with premium multi-hull designs. The hydrofoil system generates the lift under the hull, allowing for superior, stable sailing in rough water conditions.

The hydrofoil reduces friction and dragging on the hulls, reducing your fuel consumption by as much as 40% compared to other models with a similar dual hull design. The foil fits between the sponsons, featuring design and construction with stainless steel.

Another interesting design feature with this model is the way the inboard motors have positioning towards each other. This configuration allows for maximum thrust for the propellors on the asymmetrical multi-hull.

Insetta 35 IFC Hydrofoil

The foil and motor setup design also allow for much tighter turns than you get with other multi-hull models, giving you similar performance to what you expect in a mono-hull design.

The boat comes with a large coffin box with 156-gallons of space available and an insulated finish. You get eight rod-holders positioned in the bow and aft of the boat. You also get dual 30-gallon transom live wells and an option for a third below the mezzanine seat.

The Insetta 35 IFC hydrofoil comes with a three-pump sea chest, a folding bait station, and plenty of tackle storage. The boat gets its power and performance from dual Mercury 400 Verados, with the vessel topping out at speeds of 58-mph on open, calm waters.

Invincible 46 Cat

This model is the largest in the Invincible range, and it’s a great choice for offshore fishing. This flagship model comes with a 42-foot length and a center console design for easy driver operation. This multi-hull powerboat relies on a hybrid semi-asymmetrical multi-hull giving it great turning capability and maneuverability out on the open water.

Invincible 46 Cat

The Invincible 46 Cat features a stepped hull with fast acceleration and plenty of lift. You get a quad engine setup with Mercury 450 Racing outboard motors, and the craft can reach a top-end speed of 78-mph. Other notable features of this boat include a vacuum-infused hull and grid-stringer system for an “invincible” boat that’s virtually unsinkable.

Bali Catspace

If you’re looking for a luxury powercat model, the Bali Catspace Motoryacht is a fantastic – but expensive choice. This model features a design from legendary boat maker Olivier Poncin. This model is a natural cruiser and ideal for the longest ocean-going trips.

The dual hull and high ride height from the water provide exceptional stability for the boat, even in the roughest offshore and coastal waters. The boat comes with a lounge on the deck, and there’s plenty of room around the center console cabin to walk the length of the boat on either side of the vessel. The top level of the boat features the captain’s station and wheelhouse, with luxury living quarters underneath.

Bali Catspace

You get a huge lounge and a v-berth with sleeping quarters for spending the night out on the water. The cockpit presents the captain with a 360-degree view of the water, and the high riding position gives you a view of the ocean that extends for miles.

The boat comes with all the amenities you need, including tables, a full kitchenette, and luxury sleeping accommodations. There are plenty of entertainment options for TVs and stereo systems down below, with an optional hardtop Bimini.

The Bali Catspace Motoryacht receives its power from a single or dual engine setup featuring 150-HP or 250-HP Yamaha motors.

Wrapping Up

With so much variety available in multi-hull powerboats, you have options for any activity out on the water. These boats are more common in coastal waters, and they make excellent fishing vessels.

Decide on the model that suits your activity, as most have a purpose-built design for fishing, watersports, or cruising. There are plenty of customization options, so make sure you keep a budget in mind as the additions can cost more than 20% of the boat’s initial sticker price, increasing your costs.

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John is an experienced journalist and veteran boater. He heads up the content team at BoatingBeast and aims to share his many years experience of the marine world with our readers.

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diy power catamaran

Turning Nissans and Teslas into a DIY electric catamaran: Part 1

Read how UK marine electric propulsion consultant Jamie Marley designed and built his dreamboat ‘Ohm’s Law’, a DIY electric catamaran, powered by twin outboard electric motors using Nissan EV motors and Tesla batteries.

A mission to promote electric boating

Jamie is a Southampton-based marine electrical propulsion specialist who has consulted and worked on dozens of projects for boatbuilders of all description for two decades.

Along with a passion for the sea and sailing, he also has a passion for protecting our marine environments and decided early in his career that replacing ICE technology with electric propulsion would be an essential part of helping achieve that goal.

In 2014 he joined electric propulsion pioneer Torqeedo as Senior Field Service Engineer and worked with them until 2018, as Project Sales Manager specializing in electrification of new and existing passenger ferries worldwide.

Jamie Marley, builder of the DIY electric catamaran

With interest in electric boating starting to take off, Jamie realized he wanted to work hands-on with a wide variety of projects and have the freedom to use the most appropriate suppliers. He left Torqeedo to put up his own shingle and start Marine Electrification Solutions , an impartial and independent electric and hybrid marine propulsion consultancy.

His mission is simple and straightforward: To promote safe, environmentally sound, efficient and sustainable zero emission propulsion systems through cooperation .

There are few people with as broad a knowledge of electric propulsion as Jamie, and he has consulted on many major projects including the first RS Electric Boats model, the Spirit 111 which carried Torqeedo’s 100,000th motor and the electrification of Queen Elizabeth’s ceremonial rowboat ‘Gloriana’.

In December 2020 he started work on a project for someone who could be his most demanding client ever. Himself.

Making the plans: what size boat?

Planning an electric boat refit is much like figuring out how to buy any boat. The first step is figuring out the use case:

  • What will you be using the boat for?
  • Where will you be going?
  • For how long?
  • At what speed?

“I was looking for something our family (Jamie is married with two boys, 10 and 14) could go out in on a sunny day off the coast of Southern England” says Jamie. “We have a few favourite places where we have a picnic and a swim, maybe go paddleboarding…and the boys love a quick run on a tube or small boogie board.”

So he didn’t need any sleeping berths, a dayboat would be fine, and none of their activities require extreme speed: top speed for safe tubing is about 15 knots (≈ 20mph / 30 kmh).  What Jamie and his family need is a steady, reliable hull for the occasionally choppy waters and enough space to hold the equipment, a cooler and a spread-out towel for lying in the sun.

Ex-workboat, 6 metre planing catamaran

Jamie figured something about 6 – 7 metres (20-25 feet) would do nicely. He started scouting around the local marinas and classified listings.

He spotted a 6 metre (20 ft) catamaran hull made by Hunter, a UK brand known for quality and durability. With a centre console and beam of 2.5m wide (8 ft) there was lots of space for the family and the water toys. It had been used as a workboat before, so the insides had taken a bit of a beating, but the structure was all in good shape.

One of the other things that attracted Jamie was the space beneath the deck. “Because it’s really a commercial catamaran hull, the deck was flush, no seams sticking up or anything…completely sealed, and all the cargo and tools would have been on the deck.” This gave him flexibility below on where to place the batteries and the access hatches.

diy power catamaran

Now it was time to think about the propulsion. From his long experience electrifying boats he knew a planing catamaran was a great hull to work with. The two pontoons mean less water resistance and drag than a monohull, which translates into smaller power requirements and increased range.

The other advantage is that the power requirement can be split between two motors, one on each side. That was good for two reasons. One is redundancy – if there is any issue with one of the motors, the other can propel the boat. Also, he would be able to experiment and tweak each motor separately when he built them, to find the optimum set-up.

Doing the calculations: use case

Let’s look at the power usage for the boat. To do that, we need to begin with calculating the energy usage. And to do that, we need to look at a use case.

Typical use case: It’s a sunny weekend day so the family wants to get out to one of their favourite spots for a nice lunch, some swimming, sunbathing, paddleboarding and maybe some tubing. The tubing and planing speed are what require the most energy in a boat.

Let’s start our energy need calculations with that.

With 10 minutes at planing speed they would be able to travel about 3.5 miles (5.6 km) from port – plenty for what they need. Once there, the boat would use almost zero energy during swimming and paddleboarding, would need energy for the 10 minutes of tubing and another 10 minutes at planing speed to return home.

That is the upwards end of the energy required. There is every possibility that on a sunny day they would be quite happy to enjoy a leisurely cruise out to and back from their swimming spot. And at cruising speed the spots they could visit would be considerably farther from port.

Planing: 2kW of power per 50 kilograms of boat

A rule of thumb is that it takes about 2kW of power per 50 kilograms of boat to get it planing. It depends on the shape of the hull, and a catamaran is going to be more efficient than a monohull, but this is a rule of thumb. (This equation roughly translates as 2.5HP for 100 pounds of boat). Calculation:

Jamie figured the hull and two outboard motors would weigh somewhere around 1,500kg (≈3,300 lbs). That’s 30 ‘parcels’ of 50 kilograms, so multiplying that by 2kW of power means 60kW for planing speed.

This turns out to be a fairly easy number to work with, because if getting the boat on plane takes 60 kiloWatts of power, in an hour of planing it will require 60 kiloWatthours of energy – which works out to 1 kWh per minute.

So the thirty minutes of planing Jamie might need is going to require 30 kiloWatt hours of energy. He will need batteries with at least that much capacity. To make sure he always has enough energy, let’s double that and say Ohm’s Law is going to want a battery – or batteries – with 60kWh of energy storage.

Next: Battery weight

Part two of the calculation is the weight of those batteries. For that we need to understand energy density – how much energy can be stored in what weight of battery. A good rule of thumb for a lithium ion battery is that it takes 5 kilograms of lithium ion battery to store 1 kilowatt hour of energy.  So 60 kWh of energy is going to be stored in (roughly) 300 kilograms of battery.

We’d better circle back here, because our calculations were based on the boat weighing 1,500 kilograms. Now we’re at 1,800 kilograms and we haven’t got Jamie and Vicky and the kids and paddleboards and the lunch on board yet!

Let’s say the people and their paraphernalia add another 300 kilograms. Now we’re at 2,200 kilograms and we need to revisit our planing power.

2200 kgs is 44 ‘parcels’ of 50 kilograms, so we are going to need 88 kilowatts of power…but then we are going to need more battery…you can see how this can be a bit like chasing one’s tale, but it is a calculation that needs to be done.

In the end, when Jamie worked out his use cases and built in some extra capacity for more planing or unexpected emergencies, he decided to go with 120 kilowatt hours of battery storage – 600 kilograms of battery weight – to make a total boat weight of 2,500 kilograms.

Total weight: 2,500 kg / 5,500 lbs

You’ll notice that we haven’t talked about the power of the motors yet. The reason is that we needed to know the total boat weight before we could figure out the power requirement and we couldn’t figure out the boat weight until we figured out the energy requirement.

We now know we’ve got 2,500 kg of total boat weight, which is 50 parcels of 50 kgs. When we multiply that by 2kW we need 100 kw of power for planing speed.

Finding the motors

Even though Jamie was not going to be doing a lot of planing, there are lots of reasons, you don’t want any drive train – electric or fossil fuel, on a car or a boat – working at maximum output all the time. Jamie knew he needed extra power available above 100 kw, and figured that 120kW of power would give him plenty to do any planing and easily handle the cruising speeds.

One of the nice things about a catamaran is that it naturally has two motors – one on each pontoon – so the full weight of the boat doesn’t always have to be borne by one motor.  Two 60 kW outboards would fit the bill for Ohm’s Law. And for redundancy, if he did happen to have any problems out on the water with one motor, he could easily get to shore running with just one.

Creating the electric outboards

The power of a Nissan Leaf motor matches up nicely with what Jamie needed. One EV motor for each outboard. Time to start looking in detail at that.

Fossil fuel outboards have a combustion motor – the powerhead – under the cowling at the top of the setup. That motor turns a vertical shaft in the lower leg – or lower unit as it is called in North America – which in turn uses a right angle gear connection to turn a horizontal shaft with the propeller on the other end.

To convert it to an electric motor, the ICE powerhead will be replaced with an electric motor.

Simple concept, but in practice it is more complicated, because it involves precise engineering to link the existing spline on the lower leg’s shaft with the one on the electric motor to match up exactly as the original combustion motor did. It also involves calculations about the RPMs of the original motor and the new electric one.  Finally, the torque properties of an electric motor are different from ICE, so that will need to be looked at.

diy power catamaran

Jamie had the Nissan motors, the hunt now was to find the casing and lower units from a petrol /gas motor. He found what he wanted at a sale of marine equipment at the UK Ministry of Defense, and picked up a pair of used Mariner Optimax outboards.

He wasn’t concerned what shape the powerheads were in, of course, but he knew that since the  motors had been used by the Ministry they would have been well maintained with gear lubrication and all of the other things that would assure the lower shafts and gears were in good shape.

Getting ready for Part II – putting it all together

We’ve covered a lot in this article. To recap: Jamie has found his boat, done his energy/power calculations, and sourced a couple of outboard casings. Basically he has taken an assortment of ‘shell’ components for a boat that ran on fossil fuel and is now going to clean it all up with electric propulsion.

We will pick up the next stage of the Ohm’s Law journey in a Part II  Plugboats article. It will cover the details of finding the Nissan motors and Tesla batteries, converting the outboards to electric, placing the batteries in the hull, testing, re-testing and getting Ohm’s Law ready for her maiden voyage.

If you found Part 1 of this article through social media, Part II will also be posted there. Keep your eye out.

Or, why not sign up for the Plugboats newsletter below and you’ll get Part II and all the latest electric boat and boating news delivered to your mailbox every couple of weeks.

Enter your email address and click ‘Subscribe to Plugboats’ to be added to our mailing list.

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WE SPECIALIZE IN BOAT PLANS FOR AMATEUR BUILDERS

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, although several have done well in racing. All designs are suitable for amateur boat builders.

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diy solar

Sailing Catamaran Power

  • Thread starter El Guapo
  • Start date Jun 21, 2021
  • Jun 21, 2021

Hello, My family and I recently purchased a sailing catamaran and we are experiencing challenges with power generation/storage and are hoping to find some help. Here are the existing system specs: 6 - 6v 220ah batteries (I don't know how to test battery capacity/efficiency but am growing increasingly concerned that the batteries were not well cared for or the two years of non-use has drastically reduced the useful life. ) 2 - 140 watt solar pv panels 4 - 100 watt solar pv panels I just installed a new 170a Balmar on my stbd eng and this has proven to be the one thing that keeps us going as the solar panels aren't charging/keep up with our demand. I understand the pros/cons of lithium and have determined that I don't want the fire hazard on board. Zinc-ion doesn't seem to be an option yet so I may have to stay with AGMs? I completed the attached energy audit but it seems really high to me. I was thinking about bringing the house battery bank and solar pv input up to around 1100-1200 watts, keeping the Balmar on a single engine, and adding hydro/wind generation capacity hoping this will round out the system. Based on the attached audit and the above description, does anyone have any feedback? Anything I have not considered but need to? How can I test if my existing batteries are good and is there a way to add the additional +/- 600 watts that I want to add without replacing all batteries? (or if the batteries are bad, I will likely go with 6 - 6v 400ah AGMs unless someone has a different solution). I appreciate any help/input. Kindly, Kevin Fort s/v Blue Shadows www.blueshadowsadventures.com  

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  • Energy Audit_BlueShadows.zip 81 KB · Views: 6

snoobler

Solar Honey Badger

Welcome to the forum. LFP is no more dangerous than AGM. You only only 4kWh of usable battery capacity (50% of rated), which is pretty anemic. It is really high because it is. 6 hours of A/C and three hours of a water maker is VERY demanding - those two items alone are 11kWh - over half your load. If your goal is to power everything with solar, you need the calculated 4800W. You'll also need a lot of expensive solar charge controllers = about $2500-3000 worth. Regardless of source, you've established that you need 20kWh of energy daily. That's 10 hours on the Balmar. You might be getting 3.4kWh from your existing panels provided they are configured correctly and shading is not an issue. Tiny wind turbines you see on boats (not the 6-7' diameter turbines) produce very little power even in decent winds. Let's say 100W for 12h/day. that's another 1.2kWh. Not sure what you get with hydro, but you have a big gap between 20kWh and 4.6kWh you get with solar/wind. Assuming nothing from hydro, 15.4kWh will need 7.5 hours of Balmar running to supply all loads. This also assumes that you produce the power at the right times and have suitable storage. 12V is also very challenging at these demand levels... currents are VERY high. It might help to separate out the high load things from the low load items, i.e., Water heater, A/C and Water Maker all require you to run the Balmar. If you take all those things out, you only need 7.5kWh/day - a little over 1/3 the total need, and you're almost half way there already with wind and solar.  

Diysolar123

Solar addict.

you could try and just test your batteries using an internal resistance tester/analyzer...they are not that expensive and give a good hint as to the health of the little critter. these are less than $100 on ebay (SM8124A Portable Battery Internal Resistance), obviously not "laboratory grade" gear here but it should provide a hint hehe  

newbostonconst

Solar enthusiast.

  • Jun 22, 2021

LifePo4 is safe and no acid/maintance to deal with. It is to bad there isn't an easy way to take the heat from the AC and make hot water.... I don't see how you are going to get to your goal even if you covered every inch of the boat with solar. You need to do a major cut back, limit computers, AC, water..... How many people do you have on the boat? Are you Bluewater sailing 24/7 all year around? Wish you luck and we hope to be where you are some day soon....  

Snoobler - thank you. your reply was very helpful and pointed me in the right direction for continuing my research. Diysolar123 - Thank you, that tool may prove useful. newbostonconst - I agree, it would be really neat to convert a/c heat to hot water. My diesel engines do this now but it is not efficient or environmentally friendly. We are a full-time bluewater cruising family and spend 365 days/year on the boat. My wife and I run our business from the boat. Most of the time, it is just my wife, our 7 year old son, and myself on board. Occasionally, we will have 2-4 additional guests for a couple of weeks at a time. I did a lot of reading last night and am feeling more curious and open the LFP. I am also starting to think that I should seriously consider a 24v conversion of my house bank. While I don't want to say money is not an issue, I am in a position to make a reasonable investment to try and get our power generation and storage capacity closer to our consumption. I do think there are some opportunities to cut back on consumption but I'm still really surprised by how high the numbers came in on the audit. I estimated "high" on usage hours to try and provide a buffer but even still, it seems incredibly high for what I feel is an actual amount of usage. Being new to cruising, perhaps we still need to shake our "landlubber" electrical usage habits and learn "cruising" electrical usage habits... I just bought a brand new Freedom XC 2000w inverter and Outback Flexmax 80a controller. The Outback would be usable on a 24v system but it looks like I would have to find a different inverter/charger to replace the XC 2000 if I convert to a 24v system. I will also have to see if my Balmar would still be usable. I'm thinking we might nurse our current system as we sail from Northeast FL to Maine and spend the winter months in Maine designing and installing a proper 24v LFP system and try to bring my ah up to as close to 1100-1300 as possible on both the battery bank and solar. As I have come back to many times, wind generation on a boat just seems inefficient and noisy. I like the idea of hydro generation but I would prefer to look at a full conversion to electric motors that combine hydro-generation. That is a $60k upgrade to the boat however. If you guys have any thoughts you feel are important for consideration with the 24v conversion, I greatly appreciate your time! All my best,  

You will have no money lost in batteries because they can be configured to any voltage and the Flexmax is a good choice for charge controllers and flexible. You could always keep the 2000 watt inverter as a backup. You will need a DC to DC inverter to still run your 12 volt stuff if you go to 24 volts or higher. Not sure in your situation is worth the upgrade. The Flexmax will more efficient at the higher voltage you go but not ground breakingly. I do think if you made the jump to go higher voltage, I would just go right to 48 volts or even closer to 60 volts. 2/3rds of your usage is in AC so that is good. What if you kept a small 12 volt system plus a 48 volt AC system? Is that a option on the boat as far as wiring and equipment placement?  

El Guapo said: Snoobler - thank you. your reply was very helpful and pointed me in the right direction for continuing my research. Diysolar123 - Thank you, that tool may prove useful. newbostonconst - I agree, it would be really neat to convert a/c heat to hot water. My diesel engines do this now but it is not efficient or environmentally friendly. We are a full-time bluewater cruising family and spend 365 days/year on the boat. My wife and I run our business from the boat. Most of the time, it is just my wife, our 7 year old son, and myself on board. Occasionally, we will have 2-4 additional guests for a couple of weeks at a time. Click to expand...
El Guapo said: I did a lot of reading last night and am feeling more curious and open the LFP. I am also starting to think that I should seriously consider a 24v conversion of my house bank. While I don't want to say money is not an issue, I am in a position to make a reasonable investment to try and get our power generation and storage capacity closer to our consumption. Click to expand...
El Guapo said: I do think there are some opportunities to cut back on consumption but I'm still really surprised by how high the numbers came in on the audit. I estimated "high" on usage hours to try and provide a buffer but even still, it seems incredibly high for what I feel is an actual amount of usage. Being new to cruising, perhaps we still need to shake our "landlubber" electrical usage habits and learn "cruising" electrical usage habits... Click to expand...
El Guapo said: I just bought a brand new Freedom XC 2000w inverter and Outback Flexmax 80a controller. The Outback would be usable on a 24v system but it looks like I would have to find a different inverter/charger to replace the XC 2000 if I convert to a 24v system. I will also have to see if my Balmar would still be usable. Click to expand...
El Guapo said: I'm thinking we might nurse our current system as we sail from Northeast FL to Maine and spend the winter months in Maine designing and installing a proper 24v LFP system and try to bring my ah up to as close to 1100-1300 as possible on both the battery bank and solar. As I have come back to many times, wind generation on a boat just seems inefficient and noisy. I like the idea of hydro generation but I would prefer to look at a full conversion to electric motors that combine hydro-generation. That is a $60k upgrade to the boat however. Click to expand...
newbostonconst said: You will have no money lost in batteries because they can be configured to any voltage and the Flexmax is a good choice for charge controllers and flexible. You could always keep the 2000 watt inverter as a backup. You will need a DC to DC inverter to still run your 12 volt stuff if you go to 24 volts or higher. Not sure in your situation is worth the upgrade. The Flexmax will more efficient at the higher voltage you go but not ground breakingly. I do think if you made the jump to go higher voltage, I would just go right to 48 volts or even closer to 60 volts. 2/3rds of your usage is in AC so that is good. What if you kept a small 12 volt system plus a 48 volt AC system? Is that a option on the boat as far as wiring and equipment placement? Click to expand...

rin67630

snoobler said: You might be getting 3.4kWh from your existing panels provided they are configured correctly and shading is not an issue. Click to expand...
rin67630 said: Shading is ALWAYS an issue on an sailing boat. Click to expand...
snoobler said: Agreed. Mentioned to qualify the claim. Click to expand...

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

    This POWER CATAMARAN was designed to be built using the FIBERGLASS panel construction or ALUMINUM using our CUTTING FILES and boatbuilding techniques. Special pre-scaled drawings are supplied for each hull panel making it simple for the builder to build all of the hull and superstructure as one complete unit. This can be built as a POWER-SAILER ...

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