catamaran float

Hello,
I am an open water swimmer and would like to find some catamaran float plans. I was given some floats that were used to stabilize paddleboards for wheelchair users.
I'd like to reproduce the model or make it look like one.
With a construction plan and 3D parameters, I could probably have it cut by a professional CNC or make a mold.

I have no idea how to do this?
The model I'm showing you and which was given to me is made of foam.
Each float measures around 60 cm.

Thank you for your help.
Nicolas

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The book "Building Outrigger Sailing Canoes", by Gary Dierking has several construction methods and plans for outrigger floats, including polystyrene foam with a ply shear web. scale to the size you require and join with simple cross beams.

 

2nd getting Dierking’s book

I used it for inspiration for canoe outriggers for safety in winter paddling.

Mine are pink polystyrene with pvc tube connections. About 4’ long.

The foam is cut and sanded with 40 grit floor paper after bonding with pl foam glue. Then skinned with epoxy and light 4-10 oz glass.

 

4" PVC drain pipe will do it but you need shaped bows or it will plough. Easy enough to do as long as they have enough buoyancy for purpose. If not, 6" or 8".

 

Sorry, but I see this PVC pipe idea again and again (and not just for boats), and I get the shivers every time. Sure, it's cheap, quick and easy, but it's not designed for dynamic loading and its failure mode is sudden and catastrophic. I'm not an engineer, but I have enough first-hand experience. Please choose something else.

 

Nicolas,

Welcome to the Forum.

Why?
You have a catamaran float already???
Which is of questionable design.
A single float would be better.
I designed and built one for an endurance, open-ocean swimmer.

Why do you want such a big, heavy, cumbersome float with such a large wind profile (windage)?
How do you use it?
What do you carry?
Water, cell phone, food, flares, EPIRB, SPOT, LIFE-LINK?
Tell us more...

 

Thank you C.Dog for the information. I am a complete novice. I will look for this book.

 

Thanks for sharing your knowledge, I'll take a look at what I'm going to do.

 

Thank you for sharing

 

Perfect. Thank you for your time.

 

---------------
Hello,
Thank you for your welcome and for your replies. I'll try to explain.

- I was given two polystyrene floats. They were used to stabilize a wheelchair-bound paddleboard (see photo).
- The person in charge drilled holes for 2 carbon fiber tubes and glued them in place with epoxy glue.
- I installed a net in the middle.
- I added tubes in the center, forming an arch, to install a GoPro camera.
- I made a daggerboard for the stern and at the same time there's a mast with my flag.
- On the net between the two floats, I put my thermometer, water bottles, GPS, lights for my safety, and other small equipment.

In the middle of the forward tube, I put a rope. It's attached to my belt and I swim with the catamaran in tow. It's very light, I don't feel it and it offers little resistance. At the moment it's very good and I'm very visible. I'm very safe with it and people can see me from a distance.

Since I was given the floats, I don't know how to make others and improve my machine. My cats have been clawing at the polystyrene, so it's crumbling.

I'd like to find some float plans to build another one, maybe in polystyrene, maybe in fiberglass, I don't know which is better. I want it to be light to carry, strong enough to withstand shocks, and I also want to be able to decorate it, paint it with my colors and add other structures to put my GoPro cameras.

The floats are about 60 cm long.

I'm a member of a FabLab and can use a CNC for woodworking, a laser cutter and 3D printers. I made parts with a 3D printer to mount my GoPro on the tubes.

That's all I can say about my machine.

Thanks for sharing your ideas, comments and suggestions.

 

Nicolas, you're welcome.

Thank you for the explanation.
I guess you just have to build what you need.
Best of luck, keep us posted!

BB

 

Just in case you're not aware, there are dozens of different designs made from different materials for pontoons like that, which can be purchased from internet retailers like Amazon. Some are inflatable which makes them compact, lightweight, and easy to travel with, and others are made from solid materials like polyethylene, Etc . They come in different sizes, and are used to stabilize kayaks, canoes, sup, Etc. Usually by a clamping system of some kind. Seems like it would be easy to build a net platform that could utilize whichever of those existing pontoons, fit your needs.

My guess is that using a simple buoy design might be a better way to approach what you are trying to do, especially if you should be caught swimming in conditions of wind and waves. Lightly loaded pontoons can easily capsize, and can have more tow resistance due to larger surface area above and below water. Small and lightweight pontoons that I have towed have inferior tracking probably because the conditions that each individual pontoon is exposed to is not identically replicated, so sometimes I get swings side to side, or a continuous pull to one side or the other.

Hope this helps.

 

--------

Hello,

Thank you for your answer.

I was using a swimming buoy, however, one day, a Jet Ski passed less than 1 metre to my right and coming from astern. I thought I was going to die and I was incredibly scared because of his carelessness. In addition to my buoy, I had an early prototype raft attached to a 5-metre rope, supported by fluorescent-pink "pool noodles".

Since that day, I've decided to make it even more visible from afar, with a mast supporting a flag and lights. That's how my project came about.

Now I'm just looking for float plans to improve my model.
- I want it to be solid (polyester, fiberglass, wood, other composite material). Nothing inflatable.
- It has to be fairly light (easy to transport).
- With a net between the 2 floats, I need to be able to put a bit of load (water, GPS, camera, phone, thermometer, waterproof bag with my stuff).

The tests I did with my model in the photo are very good. They meet my needs. I'm highly visible and recognizable from afar. What's more, in the event of a problem, I can easily hold on to it. There's no risk of it bursting and sinking, unlike swimming buoys. The volume is greater. I don't feel any resistance. However, in the waves, I can feel the float moving, but it's not too annoying.


I added a removable 3D-printed fin.
Currently there are 3 tubes. The rear one supports the centerboard and the mast with my flag and light. The middle one supports an arch where I can install my GoPro. The one in front supports the rope connected to my belt.

With a manufacturing plan I'll be able to improve the structure above so that all the parts can be dismantled and the tubes fitted in a few clicks.

That's why I'm looking for plans.

I don't know if there are any special features I need to know about. Surely different types of models for different sailing conditions. I don't know anything about it.

Where can I find models on the Internet?
Is it possible to print in 3D?
Is it possible to cut polystyrene with a CNC?
Is it better in fiberglass?
Is wood better?
What other composite materials can I easily use?
I want to be able to paint the floats, apply stickers, etc. I'm starting from scratch.

I'm starting from scratch.

Thanks for your suggestions and plans, links if you have any.
I'm pretty handy with software and 3D.

I look forward to hearing from you all.

Thanks in advance.
Nicolas Knap

 

Thanks for the detailed explanation. Looks like you have some good ideas worked out for your particular sport.

My particular interest is in small one-man boats, and the smaller and lighter the better because I enjoy traveling and exploring different waterways while traveling throughout the USA.

"I was using a swimming buoy, however, one day, a Jet Ski passed less than 1 metre to my right and coming from astern. I thought I was going to die and I was incredibly scared because of his carelessness. In addition to my buoy, I had an early prototype raft attached to a 5-metre rope, supported by fluorescent-pink "pool noodles".

Since that day, I've decided to make it even more visible from afar, with a mast supporting a flag and lights. That's how my project came about."

I can sympathize with your experience about nearly being run over, as I have had several similar close incidents in the past. It's happened to me while fishing in one of my e-powered float tubes, even though I am plainly visible, well above water level. My guess is that sometimes it's because of them driving while impaired on meds, booze, etc., other times it seems like it's youngsters feeling adrenaline that don't have good control at speed? Sometimes, I would see them come too close to divers flags. For a time I contemplated using a strobe mounted on my hat, or even a handheld air horn to let them know they were getting too close. Then a couple of decades ago, I decided just better to avoid waterways which have lots of fast, noisy, stink pots, as those weren't conducive to my enjoying nature and having relaxation...

Anyway, be careful out there, fast moving boats may not be able to see your tow rope, or your lower water level swimming position! Especially if they approach rapidly from behind your pontoon device.

Good luck with your project!