beach catamaran hull plans

so there's three threads happening about folding cats!
the hulls can be folded under (Richard Woods) , or over (batcat),
they can fold in (Kurt Huges, cat2fold) or the other way (Bernd Kohler).
And fanie has his way of doing it, folding it up in the middle

mine most resembles Bernd's .......

Are there any other ways of doing it?

 

If the hulls not big enough to get inside, why make them hard,
make them inflatable, that is the ultimate in portability.

Or roll them up and store them in back/front of the cabin

 

That is an idea, and "Crazy Russian" did that in the last UFC, the 1200 mile Watertribe Ultimate Florida Challenge



I'd be using my hulls as storage, possibly even using the center platform for storage as well. I want nothing on the deck to get lost, just in case ...

 

How about foldable and amphibious at Kelsall Cats

http://www.kelsall.com/Designs/KSSAK18.htm

 

He also has his "trail and sail" series:
this is the xkat: beams slide in
http://www.kelsall.com/Designs/KSSNewXKat26.htm

 

Derek Kelsall came out with his Amphicat designs at the same time as I drew the Wizard. Maybe a case of "great minds think alike"

For my Wizard originally had a built in launching trolley. My thinking was, aeroplanes take their undercarriage with them, why not a boat?

But it didn't work too well so I took the wheels off after the first year

I sketched a folding cockpit/beam system for my 20ft Acorn design. But it was heavy and complicated so I decided a telescoping trailer made more sense on a smaller boat.

A boat is for sailing, not folding. The ideal is to have a folding system that doesn't compromise the boat, so when sailing it is the same as a boat that doesn't fold. That means it must weigh no more than a rigid boat and of course cost no more. It mustn't squeak or move when underway. Propane hoses must stay intact. Engines and batteries cannot go on their sides. Winches and lines mustn't foul the folding system. There's a lot more to think about on a bigger boat than on a daysailer.

The further it is from the ideal the less successful the boat. And I think a big folder is too far from ideal. No design is perfect, so you have to start with an ideal concept and then work down from there. In other words a big folder catamaran maybe could be done. Just never efficiently nor cost effectively

Richard Woods of Woods Designs

www.sailingcatamarans.com

 

It all depends on just what the requirements are. Different boats for different purposes. And presently I'm the only one on the planet with my requirements. Will it accomplish it's goals? I believe it will. Will it ever compete as an F16 or other class racing, never. Will it travel for weeks on end with all of my gear yes. Will it be easier to build than a full sized cruiser? Yes. Will it ever be a commercial success? Not it's purpose in life.

There's a heap of problems to over come on a full sized folding cat but just because it's not main stream doesn't mean it can't be done. I got hope for those guys out there giving it a try. Cat2Fold shows it can be done, so I hope that's inspiration to those that haven't given up hope yet. It'll never be a racer, it'll never be a lot of things, but if folding is important enough, then so be it and have at it.

Anyway, once I have my prindle 16 test mule built and sailing I'll have a better idea of the hull requirements and can focus on that then. It doesn't have to please the world, just me. So far no existing design seems to work? but I won't know that til later. I might have a designer help me out when the time comes. Presently I'm thinking symmetric hulls, F16 style but 2 feet tall and with a bit more volume. Once I know the weight of a fully loaded boat I can go from there.

 

Your boat has a very special niche. That purpose is important to you wo go ahead with the idea. Richard obviously isn't against folders, since he has them both in cats and tris. With the interest in Frank's folding tri, perhaps you can adapt some of that approach into your cat?

Dan

 

Sounds a bit strange but as a trimaran the F16 hulls are not ideal, particularly if you plan to load the beast up with kitchen sinks and the likes.

Have a look at Indian Canoe designs which have a relatively wide hull section, about the right length and with very light weight Amas , could suit your purpose.

Incidentally Phyll Brandar designed two home builds, one the Blade which was a glass foam construction and his later design which I cannot remember its name, was a ply based design. There are a few Blade plans about that have come up for sale over the years.

Why reinvent the wheel when you can buy an older A Class with all its rig and fittings, extend it at the rear a bit and job done.

 

I'd love to have an 18 foot A class boat! but remember that I got to portage it over 40 miles!

I'm pretty set on a cat design for a number of reasons, 3' width for portage, narrow enough folded to get thru tight waterways. High and dry in either position so I can get some sleep on it, even while portaging!

I just haven't seen how a tri could do all these things.

and I've been in contact with the blade guy and he's coming out with the Razor soon, it's got more volume as he describes it.

btw, I'd not be loading up the kitchen sink, think backpacking! Drinking water would be the heaviest thing I carry. Here's me almost at the end of a 5 day race pace type Adirondack adventure. Believe me, when you got to carry EVERYTHING for up to 3 miles at a time, you look at every thread weighing you down. I won't be this bad for the EC or UFC but close.

I'm a pretty good paddler and everyone wonders why I don't just paddle the 1200 miles?! If I was to do it this year I would, no water in the rivers! Otherwise this is as much as an engineering challenge as it is a race. ...... and don't get me started on the "boat switch rule"!

 

The A class is around 75 kgs all up, remember they are all about the lightest weight cat you can get with good durability, complicate things with folders etc and you can only get a heavier all up package. Practice on dismantling the beams and for the bit extra in time, it may save you considearble in weight.

I made a poor error earlier, it was not the indian canoe but the IC or International Canoe, do away with the sliding seat with short amas as training wheels and you have a reasonably load carrying light weight stable platform that is ever so fast.

 

Here is another folding cat, I saw them unloading it in Richmond recently,



One point of interest is the use of combined inflatable and ridged hulls

 

Now this is an interesting concept! bet it would paddle well too? but where would the rigging be stowed while I'm paddling for a hundred miles or more? It's got to get up the St. Mary's river, then down the Suwannee and back into the gulf, rig for sailing again and finish stage 5. Oh yeah, there's the 40 mile portage in between the rivers.

 

Well there'd certainly no dozing off while underway on this little demon!

 

Now that's something to look at! Got any more pics? it would be nice to see it going thru the folding stages. that's one honkin' party barge!