Designing a sailing dinghy for expeditions

Discussion in 'Boat Design' started by BoraBoats, Feb 25, 2019.

  1. DCockey
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    DCockey Senior Member

    BoraBoats - More questions:
    Will your boat need to meet the EU Recreational Craft Directive? Have you investigated potential requirements such as freeboard, stability and floatation if swamped?

    Which boats or designs currently available are you using as references and benchmarks?

    How did you arrive at 60kg? Are there any similar boats currently available with that hull weight?
     
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  2. Squidly-Diddly
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    Squidly-Diddly Senior Member

    I'd like to see a Universal Sport/Expedition Dingy. But not so much "expedition" as in epic open ocean crossings.
    Something equally suited to outboard, rowing or sailing.
    Equally suited to fishing, hunting, camping, day sailing or cargo.
    A jack of all trades. About 16-20' long and able to semi-plane with sails or outboard.

    Dual purpose dagger-boards that can function as gang-planks, rudders, spud-poles, table-tops, bench seats or (whatever those things are that people use to hike-out on a small sailboat to go fast in high wind). One size and shape that can interchange for all those functions.

    Provision to easily rig sails as awnings, both sun shade and water shedding tent.

    Small cuddy for storing gear and (barely) sleeping.

    To get the hull shape maybe take a MacGregor 26 and chop it about 20" from keel with a little rise toward the bow, then shrink it to right length and all dimensions with softwarz.
     
  3. Angélique
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    Angélique aka Angel (only by name)

    Again all good questions in post #16 David, that need to be answered for a successful concept . . :)

    It would also be good if Emilie set up or posted a SOR (Statement of Requirements).

    The below design doesn't meet all so far posted requirements, but for the weight it could be a start to look at, a Blivit 13 has a bare hull weight of 60 lbs (27.2 kg) and an carrying capacity of 700 lbs (317.5 kg), which covers a ± medium sized crew of 4, or 2 with a lot of camping gear...

    [​IMG]

    Geodesic AiroliteBoatsConstruction & MaterialsBlivit 13SpecsTestimonialPics
     
    Last edited: Feb 27, 2019
  4. Angélique
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    Angélique aka Angel (only by name)

    Michael Storer's 12' (3.66 m) × 4' (1.22 m) Oz Goose* covers a lot of the so far posted requirements including weight I think, but maybe for some it doesn't look so modern or sporty, but despite her kinda non sporty looks, she's actually quite sporty and could be an inspiration...

    (* inspired by the ± 8' (2.44 m) × 4' (1.22 m) Puddle Duck Racer, aka PD Racer, aka PDR, and the Oz RacerMK II.)

    [​IMG]
    note the to be built in internal flotation chambers on both sides, for positive flotation for the crew and gear when the boat gets swamped.

    [​IMG]

    Michael StorerOz GooseOpen Goose . comDuckWorks: Discovering the Oz GooseDuckWorks: Oz Goose Plans

    P.S.

    There are also cabin versions of the Oz Racer and the Oz Goose, the Ocean Explorer and the Ooze Goose, ‘‘Ocean’’ being tongue-in-cheek there though.
     
    Last edited: Feb 26, 2019
  5. BoraBoats
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    BoraBoats Emilie

    At our university we have one semester for the thesis. I did not ask if it was a good topic or not. I have already chosen it and will not change my mind. For comparison, one guy in my class is doing his thesis on the design of autonomous electric ferry and two other guys are working on concepts for a new car. I think my supervisor should know if it is a good topic for me or not. The most important is that I think it is fun and interesting. I am not going to try to be a naval architect, I will take a different approach than what a naval architect would have done. I will take a user-centered approach, and not go into the details of the hull construction as I said.
     
  6. BoraBoats
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    BoraBoats Emilie

    That looks like a cool boat! Thanks!
     
  7. BoraBoats
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    BoraBoats Emilie

    I will end up with a concept so I don't think I will care that much about th EU directive, but I will look into it. I have not set any specific requirements on freeboard and stability. It is crucial that it floats even if it it swamped. The boats I am currently inspired by are RS Aero, LiteBoatXP, LiteBoat's rowboats, international canoe (even though it is super unstable), Tiwal and Weta trimaran. RS Aero has a hull weight of 32kg. I interviewed two guys who has experience with sailing dinghies for long distances. They have been on expeditions for several weeks with dinghies. One of them said the hull should not be more than 60kg for it to be easy to handle, the other said 60-80 kg.
     
  8. Dolfiman
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    Dolfiman Senior Member

    I thought also at the LiteBoat XP when reading your specifications, but it is 150 kg light weight (boat, rig, sails), a 60 kg version is very challenging, may be with the length reduced to about 12-13 ft ?
    LiteXP | Liteboat - Light, stable, easy rowing boats https://www.liteboat.com/fr/product/litexp/
    This web site (in French) is dedicated to nautical trekking close to your programme, with a great variety of approach, of boats, of stories, that could help adjust your specifications : Nautical Trek – Le site des voileux randonneurs https://nauticaltrek.com/
     
  9. BoraBoats
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    BoraBoats Emilie

    I was planning to make it shorter than LiteBoatXP, 12-13 ft is where I am heading. Also, I am not planning to have a cabin. I am not good at french, so I don't understand much, but anyways nice to see pictures of the boats they are using :)
     
  10. Dolfiman
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    Dolfiman Senior Member

    Here another example, Jimmy Skiff 2, a 68 kg polyvalent approach, seaworthy, a traditional sharpie design but from which you can easily derived a more modern one at same dimensions and weight, the comments of the designer in this video can help you :
     
  11. BoraBoats
    Joined: Feb 2019
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    BoraBoats Emilie

    Project update 1. Background

    In 2016/2017 I spent one year at Fosen Folkehøgskole to study traditional boat building (I can recommend all of you to do the same, it was awesome!). Here I also got introduced to sailing for the first time. The first experiences I had was in open traditional wooden boats, Åfjords-boats. In these boats you got a close connection to the elements; the rain hitting your face, the waves splashing against the wooden hull and the wind pushing us forward. Many of the trips went to a small island where the school kept sheep for meat and wool production. We spent the nights around the bonfire, and some nights, if we were lucky, we could see the northern lights (picture attached is from one of these trips). It felt like this was the ultimate way of experiencing nature.

    DSC_0109 18.40.13.JPG

    After the year at Fosen Folkehøgskole was finished, I went back to the university to finish my degree in industrial design engineering. I wanted to continue sailing, so I became a member of the sailing club at the university. Here I had a completely different experience with sailing. We were practicing for regattas with ynglings, sailing back and forth between marks not far from the harbor. I thought this was quite boring, I am not a big fan of competitions and I rather wanted to go explore the coast. I realized that this is what meets most people that want to try sailing for the first time.

    In Norway most people get introduced to sailing through the optimist class, but a lot of people quit after a short time. The sailing association is struggling with keeping its members. On the other hand, outdoors activities have never been as popular in Norway as now. Ocean paddling is one of the activities that that has had a great rise in popularity during the last ten years. During this period, Norway has imported about 60 times as many kayaks and canoes as small sailboats (under 7.5m). So why do people want to go paddling, but not sailing?

    Maybe it is because there is a shortage of places for boats in marinas in Norway. Or because the sailing association in Norway has a large focus on regatta sailing which does not fit everyone. They have failed to communicate the opportunity sailing gives for experiencing nature. Also, the most popular sailing magazine in Norway, Seilmagasinet, has had their main focus on boats that are 40ft or larger. This combined creates the impression that sailing is for the elite, for the few. It is not like mountain biking, skiing or ocean paddling.

    However, during the last few years, the sailing association has started to put more light on cruising and the nature experiences you can get when sailing. Seilmagasinet has also stated that they have noticed a new trend; expedition sailing with dinghies. Magne Klann is part of this trend. He sailed an RS Aero along the coast of Norway from north to south and documented his travels in the book “Norge om babord” ( forum | General Discussion | NORWAY TO PORT! | RS Aero Class Association https://www.rsaerosailing.org/index.asp?p=forum&fid=1&tid=8067 ). This trip showed that sailing a dinghy can give you a greater experience and a closer connection to nature than sailing a bigger, more comfortable boat, and it does not need to be expensive. This new trend opens the possibility for a new market, a market for expedition dinghies.

    My goal for this project is to develop a concept for new sailing dinghy that makes sailing more available and relevant for people that are interested in exploring nature.

    Note: I am focusing mostly on the Norwegian market because I have the most information and contacts here, but if you have comments on the state of sailing as a way of experiencing nature in other countries, feel free to share.
     
    Last edited: Feb 26, 2019
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  12. BoraBoats
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    BoraBoats Emilie

    For getting into the right mood:
     
  13. Clarkey
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    Clarkey Junior Member

    Hi, sounds like an interesting piece of work. Since you are adopting a user-based approach have you identified your users? Do you have any user stories or personas that might inform the concept?
     
  14. BoraBoats
    Joined: Feb 2019
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    BoraBoats Emilie

    Yes. I will post something about it soon, but I don't think I have the time today.
     

  15. Tiny Turnip
    Joined: Mar 2008
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    Tiny Turnip Senior Member

    A couple of further things from my own experience. My boat, really a little trimaran @16ft, is about 100kg fully rigged. two of us can carry it unladen, and have done up to about 200 yards, but I wouldn't want it to weigh any more. 60kg would certainly be better. I carry a collapsible trolley, which makes things easier in some situations, but also allows the possibility of extended 'portages' which opens up a whole new flexibility in expeditions.
    The rig is a relatively modest 7.5 sqm, split between unstayed main and mizzen. This means you can reef simply by taking the boom off and spinning the mast, and makes it very difficult to capsize when combined with the 200kg buoyancy in each outrigger, but it will also do 11-12knots. I consider a reasonable turn of speed to be another aspect of seaworthiness.

    Thanks for the liteboat link. I knew the R2AK version. Interesting, but for me, 150kg is too heavy. Your target of 60kg is much better, and should be achievable in a 10-12ft boat, though I'd say that the smaller size will limit the conditions you can set forth in a little. A larger boat would be more seaworthy, faster, carry more gear, but I suspect you may have to start thinking about vacuum infusion, possibly exotic composites to achieve the weight target. Always beautiful compromises!
     
    Doug Lord likes this.
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