Deep V continuous rocker proa. version 2.0
This drawing shows the most common profile of the Marshallese walap. You can download the whole 6 MB document by Dennis Alessio here: https://dl.dropboxusercontent.com/u/21351227/wak7enewetak.pdf
Thanks Gary!!!
A great article. I have read about half of it, and it gives a very good and clear picture of the origin and design of the Micronesian Walap…
I am learning soo much from you all on this forum! It is a really great place! The learning-curve has been exponential and it is only getting steeper each day!
I have not decided on the exact design yet. There is so many factors and so many different, often conflicting, properties to optimize. When I am learning new stuff every day, it is very hard to make a decicion. Whatever I want to build today, is superseded by new knowledge and new ideas tomorrow. I have been through quite a lot of different designs already. Every time I think to myself “this is the one I am going to build!” but a day/week/month later there is several new ideas that I want to test and build….
I am still comparing the barge-proa with my deep-V, and I have trouble deciding which way to go.
Any and all input on this matter is greatly appreciated.
The barge performs so much better than I could ever belive it should, is very easy to build and has a great carrying capacity.
The deep-V is faster and “feels” much more seaworthy and well behaved in waves, and I think it is quite beautiful…
I am making some progress on my ama. Today I covered the top chine/corner with two layers of 200g/m2 fiberglass and epoxy.
Wow what a great read! It even shows how to do the illusive lashing connecting the ama to the uprights. Thanks Gary.
Every time I think to myself “this is the one I am going to build!” but a day/week/month later there is several new ideas that I want to test and build….
Welcome to the club, I think!
-Thomas
I made a small model with the right size and proportions (scaled to 1/10) of what I have in mind. The blunt ends will be smaller than on this model, as those are to large and to close to the surface.
I don’t like those blunt ends on this kind of hull. I want sharp pointy ends, but I need the longer water line length and greater displacement they add. It is a tradeof as everything else…
Cheers,
Johannes
Marshall island canoes carry their fullness really far forward. Actually, looking at some of the pictures they almost have a tiny pram-like bow.
http://starr.talkspotblogs.com/uploads/49799/Boat1.jpg
Maybe time to copy the experts :-)
-Thomas
Thanks for that link Gary, I learned some interesting stuff just flipping through it so I’m really looking forward to reading it in detail. I never realized that the keel was actually three separate pieces of wood stitched together, which certainly answers Luomanen’s question. 😉
I made a small model with the right size and proportions (scaled to 1/10) of what I have in mind. The blunt ends will be smaller than on this model, as those are to large and to close to the surface.
I don’t like those blunt ends on this kind of hull. I want sharp pointy ends, but I need the longer water line length and greater displacement they add. It is a tradeof as everything else…
The bluff bows might look better if they were angled the way that they are on your barge hull. The whole effect with the blunt ends reminds me strongly of a traditional Chinese Junk bow. A good example is Alan Farrell’s China Cloud. I think it could look quite nice if done right.
http://1.bp.blogspot.com/_FMwMBlr0Eu0/TRJ8YndKS8I/AAAAAAAAB6k/55RgYdSifHE/s1600/China+Cloud.jpg
On the other hand, you could try “torturing” your plywood a little by stitching the ends closed, possibly with the addition of a Micronesian-esque raised decorative cutwater for good measure.
Marshall island canoes carry their fullness really far forward. Actually, looking at some of the pictures they almost have a tiny pram-like bow.
That fullness might only be a widened deck for handling the crab claw sail as that picture doesn’t really show if that fullness is carried over into the hull. I think that, viewed from a lower angle, it might look more like this:
http://farm4.staticflickr.com/3208/2950578257_3f9e9fe0cb.jpg
The bluff bows might look better if they were angled the way that they are on your barge hull. The whole effect with the blunt ends reminds me strongly of a traditional Chinese Junk bow.
On the other hand, you could try “torturing” your plywood a little by stitching the ends closed, possibly with the addition of a Micronesian-esque raised decorative cutwater for good measure.
There are soo many options…..
I am thinking about your idea Greg, with the plywood offcuts on top of the gunwale, and I am considering many different ways to add some payload capacity… I want to build a 50 foot hull, but I don´t have the space to do it.
The summer is way to short here in Sweden to build it outside.
If I use bluff bows, they will be angled outwards like on my barge. Yesterday I was in a hurry to build the model, as my wife and kids was on their way home from a hike, and I had some cleaning to do before they got home.
Thanks for ideas and links to great pictures!!!
Cheers,
Johannes
That fullness might only be a widened deck for handling the crab claw sail as that picture doesn’t really show if that fullness is carried over into the hull. I think that, viewed from a lower angle, it might look more like this:
http://farm4.staticflickr.com/3208/2950578257_3f9e9fe0cb.jpg
A few weeks back I posted some pics of the Tepukei which is from the Solomon Islands. From the top at least it looks very much like tdems pic. The Tepukei has pretty much parallel gunwales and a nearly circular cross-section for the entire length of the boat, only the last little bit, less than the last 50-100cm of the length I’d say, arcs up and inward to form a bow, but otherwise the boat has a very full profile, so it’s definitely been done. Doing that should provide lots of reserve buoyancy in the bows, something which might be particularly beneficial on a design which has pretty low freeboard and is designed to be loaded rather heavily, but I’ve always wondered about how detrimental to performance bows like that might be. Maybe it’s not so bad though?
If you build with flat bows and decide you don’t like them, you can always add short, point extensions onto them later! Heck, you could add only one and see how it sails in that direction versus the other!
Heck, you could add only one and see how it sails in that direction versus the other!
That is a great idea. I do like my pointy ends though. I will have two small blunt ends on my 24 foot deep-V vaka to maximize the ability to carry some weight. I try to avoid every kind of complexity as much as possible, and I like the clean lines of carrying the rocker all the way out to the ends of the hull.
I have been trying to build a new longer and more slender deep-v vaka model, but I don´t have any energy at the moment. Today I managed to stitch the two sides together with some cable-ties.
It is going to be 195 cm long, 13 cm high in the middle with bigger keel-radius and lower ends. I want a longer water-line length and a lower center of gravity.
It is a scale model of 8 sheets of plywood long deep-v vaka.
Cheers,
Johannes
I am working in short bursts, but making some slow progress. I wish it was 64 feet long and not some small scale model.
This is my first model that will have a leepod. I am very curious how that will work out.
Cheers,
Johannes
Look at you with a lee pod. Looking good Johannes!
My tiny bit of experience sailing my tacking outrigger has sold me 100% on a device to get the boat back on its feet. I’ve use the assumptions Sven outlined in his epic stability post as a guide.
The stability of an outrigger when the akas are relatively horizontal is impressive. Not so much past about 30 degrees.
What happened to your 24’ er?
What happened to your 24’ er?
I am working on it, but very slowly. First my ama has to get to the point where I can leave it outside for the winter, then I will concentrate my efforts on my 24 foot vaka.
This model is my design I will use for the 24 footer which in time will become my 60 foot vaka.
The models has always been my way to test and learn what ideas are good and what to avoid. There are not many proas in sweden, so in order to get some understanding and experience I have to test small models for all the wild ideas, a 24 foot proa to get the hang of sailing a proa in real life, and hopefully someday I will build the big one based on everything I have learned by doing all this.
A agree with the need (absolut nessesity) of some kind of safety device like a leepod or lee/safety - ama.
For a large (35 foot or more) liveaboard proa the leepod gives a lot of additional space inside.
For a smaller proa the safety-ama seems like a simpler and better idea.
I have seen my models go turtle many times. Sometimes with such speed and furiosity that it scared me from the thought of a large proa. This is partly why I will test a leepod on my model. I want to work out all the details of the design and function in the safety of standing in one foot of water. Not while trying to survive 20 miles out on lake vänern early in May with my proa up side down.
Cheers,
Johannes
I have seen my models go turtle many times. Sometimes with such speed and furiosity that it scared me from the thought of a large proa.
Keep in mind, though, that a scale model’s motions happen √(scale) faster than the real thing. So a full sized proa would take 2.45 times longer to violently capsize and strand you in the middle of Lake Vänern than a 1:6 scale model would. 😉
So a full sized proa would take 2.45 times longer to violently capsize and strand you in the middle of Lake Vänern
That is not reassuring at all! 2.5 seconds instead of 1…..
I guess a lee-pod/ama is very important if one wants to sail in the cold water here on the 58 parallel.
Today I made some progress on my new deep-v proa-model.
Now I am back to the green color again, but it looks kind of dull and boring compared to the red color of my last model.
It is considerably heavier than the last deep-v vaka. The vaka weights 1,73 kg, and the whole proa (vaka, ama, akas and rig) 2,41 kg.
I hope I can test sail it soon.
The leepod is not complete. I will ad the rest of the pod later. Right now there is only the bottom part of the pod attached to the hull.
Cheers,
Johannes