Hi there, new idea I came up with... I think

[Vanquish86]

Hey all. I'm completely new here. I basically had an idea flash into my mind last night, and realized I'd never heard of it before. So after searching on Google to see if what I'd dreamed up existed, I figured I'd go to a message board about it.

Basically I envisioned a fishing kayak that is actually 2 separate hulls, which join together at the cockpit. The 2 hulls pivot around the cockpit, allowing the pilot to change the configuration of the kayak from a normal, single hulled kayak suitable for paddling, into an X formation which would greatly reduce the ease of tipping the craft, suitable for extended periods of time spent fishing in a stationary position.

I don't know if such a thing is physically possible, but I have such a clear vision in my mind that I really want to make a reality, I just have no idea where to start. The hull design I can envision vividly, it's the pivot point, and the placement of the pilots legs, that keeps hanging me up.


Basically, the craft goes from this: | to this: X

I don't even know if I'm in the right place lol

[alan white]

Welcome to the forum.
I can see what you're trying to achieve. I guess I don't see why you would be going about making the hull stable in such a complicated way.
for example, two basketball-sized floats weighing one pound each could be attached to the opposite ends of the paddle and then dropped into a slot that crosses the deck, locking in place. The floats would make the kayak very stable and the two floats could be lashed to the foredeck when not in use.
The problems with the hull becoming an X shape are it involves an interruption in an otherwise seamless hull and it would add a significant amount of extra weight, both of which would make paddling and portaging a lot more work. Then there would be the high cost of building the boat.
You seem to be smitten with the idea, however, and so you shouldn't take my comment as gospel, but see what I might not be seeing.

Regards, Alan

[rwatson]

Alan makes some good points, but the idea of a 'transformer' type hull may have hidden benefits.
My first take is that you could just make the rear part of the canoe split into two halves, behind the paddling position.
This would form a Y, instead of an X,and you avoid the problem of emascualting the paddler while achieving almost the same degree of stability.
Jaque Custeaou 's 'Alcyone' was a Y shape, with a mono front and a forked rear 'tail' to limit heeling to under 6 degrees.
With carefull design, you could incorporate a small outboard motor to be used in this configuration, that might be too much for the craft when in the 'narrow' mode.
This would mean you could paddle up narrow creeks and later sit out in the open ocean fishing with no fear of capsizing.
Worth a think about.

[Trevlyns]

The Y design is already patented. It's on this website. I went to try and locate it but they now require registration first - which I couldn't be bothered with.

Best!

[RivrLivn]

Here is the "split back" kayak.
http://www.freedomhawkkayaks.com/

[Chris Ostlind]

Originally Posted by RivrLivn

I have seen and demo'ed this boat at a trade show and it does everything it says it can. The guys who run the company are extremely nice dudes, as well.

No affiliation and all the standard claims apply

ChrisO

[rwatson]

Holy deja vu!

It really *is* impossible to think of something new!!!!!!!

[kengrome]

Basically I envisioned a fishing kayak that is actually 2 separate hulls ...

I designed one (more than two years ago) that had a main hull and an ama on each side for stability, in other words a trimaran. Its amas could separate -- with the forward halves moving outward and forward, and the aft halves moving outward and abaft -- thus creating the X pattern you're talking about.

In my design all four amas were connected to the main hull by wood and glass laminated akas, effectively making them work like leaf springs on a car. They would flex and absorb wave energy independently of the main hull. This would start lifting the main hull a little bit before an approaching wave gets to it, so the wave's effect on the main hull would be dampened by this advanced lifting.

The amas would also fold in and connect to the main hull for travel in very narrow creeks and such. My whole concept here was a convertible boat that could be made narrow enough to go up almost any stream, yet it could also be made super wide and stable to safely cross a rough lake without worry even in a not-too-serious storm.

I never pursued the idea, but given the American love of 'technology' you might sell lots of them, especially if they work well and don't cost too much. They could be built very cheaply the way I designed mine, although they would probably sell better at 2-3 times the price using all high-tech materials and no wood.

[Vanquish86]

Originally Posted by Chris Ostlind

I have seen and demo'ed this boat at a trade show and it does everything it says it can. The guys who run the company are extremely nice dudes, as well.

No affiliation and all the standard claims apply

ChrisO

That kayak is almost what I was thinking about, only the front would split as well, with the front / back opposite sides actually being a single piece. I was thinking the seat would actually telescope up and pivot, so the X craft could float facing any direction and the pilot could pivot on the seat to face and fish any direction they want. This way I figure it would be more comfortable to sit and fish than to stand, and the seat could be lowered back down again when the craft is converted back into a regular kayak.


I can see how this wouldn't be economical given the easier ways of achieving the same stability, it was just something that popped into my head one day when I was trying to think of a good way to fish from a kayak.

[Chris Ostlind]

Some of the stuff that the Freedom 14 gives away, in order to get the enhanced stability...

Weight: add sidewall construction down the centerline for each aft hull and molded parts for the pivot mechanism.

Complexity: More stuff to keep in your eyesight when doing routine maintenance. Hard knocks on the foldout wings, when navigating rivers, will potentially lead to a broken wing mount... unless you get those wings back into the normal configuration.

Slower speeds: Added weight, increased drag of fold-out modules will make for a slower boat. Slow is not the real issue, but the energy required to go the same distance will be something to consider. Small deal, but there, nevertheless.

Convenience of Actions: Can the folding parts be moved, easily, while on the water without feeling like its a circus act?

Reconfigured Windage: What will the boat do in the wind while fishing with lots of new surfaces on which to grab and turn the craft?

This stuff has to be balanced by the relative advantages in order to make it worth the trouble in design and build modes.

My 2 cents... I'm rather more drawn to a folding ama setup well aft of the cockpit and clear of the paddle stroke. A simple line aft will deploy the bungee loaded amas and the line is cleated-off. Done fishing and heading home? Uncleat the deployment line and the amas retract back on the aft hull deck for low profile paddling and minimized wind resistance.

Whole thing is minimal added weight to the basic kayak. Can be removed at will to restore full playboat characteristics. Replace fishing ama volume with slightly larger units and the boat can be sailed a bit for an added feature.

Chris Ostlind

[alan white]

Bearing in mind that any float device, whether an ama or a split hull, is not being used to best advantage if it is larger near the hull and tapering as it extends out.
The opposite would be lighter and simpler. If a pair of small floats were extended four feet out to each side, where their entire bouyancy could serve at maximum distance, the only problem would be how to brace them.
Windage wouldn't be an issue, nor much cost, complexity, whole boat replacement, or weight.
Poles, either wood or aluminum, could pivot out from forward near the bow.
the end of each pole would be fitted with a small float (maybe one cubic foot of air within). The floats swing from just behind the paddler to about four feet to each side of the paddler, who can still paddle easily.
Two small stainless steel cables brace the two poles. The cables are fitted to a point close to the waterline, exactly where the bobstay attaches to a boat with a sprit.
A (maybe 6" radius) quadrant (partial pulley) is affixed to the pivot of each pole. The in-out control lanyard wraps around the quadrants. Pull one (outer side of each quadrant) lanyard and the rig goes out. Pull on the other (inner side) and it comes in.
5-7 lbs maybe, $100.00 package to fit most every kayak.