Cat vs mono, advice for my case. Or multi-hull discrimination in Japan

Discussion in 'Multihulls' started by xellz, Oct 19, 2017.

  1. xellz
    Joined: Jul 2017
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    Location: Japan

    xellz Junior Member

    Originally started with idea to convert old fishing mono-hull to electric propulsion for fuel efficiency, comfort and with help from here i got to the point, that on paper it was actually viable solution for my needs, but with efficient catamaran hull.

    Long story short, after countless meetings any kind of financial help for catamaran was canceled due to prefecture officials refusing to give clear answer to if catamaran could be registered as commercial fishing vessel (same for any propulsion, electric, diesel, gasoline...). With current information most likely negative. But they gladly register almost anything that could float and move itself, but doesn't have any extra "hulls". So fully electric will be postponed until i can afford it on my own.

    Right now i'm trying to decide, buy plans for catamaran, translate, add anything of value, like which safety tests and standards were passed and let officials examine it well. Or use 50% discount to any used fishing boat that is older than 10yr. I got this offer from last meeting. Sounds good, especially with many fishermen quitting, boats are fairly cheap to begin with. But then fuel cost, maintenance and efficiency comes into play and the main reason, why so many fishermen quit appears.

    After learning about hull shapes quite a bit and readings lots of real use reports i can't help myself, but think that light efficient power catamaran is the only way to go for me. Did i convince myself too much?

    For what and how boat will be used:
    I'm living on small island with little bit over 100ppl population.
    Main will be single line bait fishing for expensive types of fish, drifting over structures. Depths from 30m to 350-400m. Trolling at low speeds 2-3knots to 6-7knots depends on target. Most common scenario is once reach fishing spot, engine on idle for 5-15min, move back and repeat for several times, move different location and continue same thing. Fishing locations are quite close, usually there is no need to go further than 10-12km, going around island is about 18km in total. Occasionally with good catch and bad ferry timing want to go until nearest large fishing port, which is roughly 60km from island. Total weight of catch is small and really rarely exceeds 100kg, although even 100kg of most species will fetch between 1200-2000usd.

    At some point want to do charter sports fishing, it requires separate license, so not right away.

    I.e. stability during drifting or low speeds and fuel efficiency are my main concerns. Few fishermen that are left use over-sized monos, 32-40ft heavy duty ships to catch less than 100kg a day of fish just doesn't sound right. Those ships burn through ridiculous amount of fuel each day. About repair costs no one wants to talk in detail, but i doubt low rpms and mostly idle is good for heavy marine diesels.

    I won't be navigating far offshore, together with good local weather forecast i don't really need to worry about being caught in heavy storm. Some rough weather to be expected, but no ship wrecking conditions.

    Local fishermen association only welcomes my idea, electric propulsion in particular and i got permissions for docking and pulling a cable for charging.




    Sorry for long post, i guess i just got burned out a bit from talking with officials about permits and promised partial funding. Never liked paper work :) Some opinions might help me get back on track. I really want to keep living on small island, but certainly it's not easy.


    And almost forgot, catamaran that i want to build is Jazz 30 by Woods Design. Sailing Catamarans - Jazz 30 fishing, day charter or cruising http://www.sailingcatamarans.com/index.php/designs-2/6-powercats/438-jazz-30-fishing-power-catamaran
    Start with outboards and when funds allow convert to electric. Outboards can be sold without too much trouble too.
     
  2. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    You are better off starting with your own design and using your own SOR.

    Sounds like typical Japanese bureaucracy, I know as I'm also in Japan! Where are you based?

    A nice slender hull with an L/B ratio 10-15 would be best and then a platform between for your catch, cockpit etc etc.

    Happy to assist if you want?

    Have you thought about where to build and what materials yet?
     
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    I'm not sure how the fuel bill would be a problem, given the distances quoted, unless trolling a great deal, and even then slow trolling typically is not fuel hungry.
     
  4. xellz
    Joined: Jul 2017
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    xellz Junior Member

    Doing custom design might add quite a bit of extra cost, 40ft+ slim and light displacement catamaran would be nice. Slim mono-hull when drifting will most likely roll badly even in small waves. But Jazz 30 is already designed, design is not custom made, so doesn't cost an arm and a leg. Material and shape is easy to work, i like the wide beam too. I also checked material estimate and got through few Japanese suppliers of marine ply. But there is no 100% guarantee that i can convince officials to register Jazz 30 as commercial fishing boat even with plans, that's what i'm pondering about.

    Kagoshima, Iojima island. Building can be done near our house, i wanted to build a shed anyway, just need to make it large enough. Got enough space.
     
  5. xellz
    Joined: Jul 2017
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    xellz Junior Member

    100-200$ per day of fuel burnt if not more, about 100-200 days on the water depends on ship and desire to work. In 32-40ft range Japanese fishing ships usually come with 200-360hp heavy duty marine diesels. Not all days provide great catch, with rising fuel prices becomes more difficult to keep decent income, while spending lots on fuel alone.
     
  6. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Sounds like you've got your boat now....all you need to do is get a quote for the design.

    Bit far from me....im in Kobe.
     
  7. xellz
    Joined: Jul 2017
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    xellz Junior Member

    But i'm quite curious roughly how much custom design could actually cost, with almost no interior design, it's a day fishing boat afterall. 30-32ft.
     
  8. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Get the quote for the boat you've now identified, then see how it sits with you....and then you'll have a bench mark.
     
  9. Mr Efficiency
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    Mr Efficiency Senior Member

    How many aboard ?
     
  10. xellz
    Joined: Jul 2017
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    xellz Junior Member

    Mostly alone, when setting up nets 2 ppl. Distances are short, but during whole day move quite a bit between spots. I won't be using nets myself, so fishing will be done solo most of the time. If i start taking in paying passengers i want to limit it to 4-5 ppl at a time. I was out fishing around island on various boats already, in calm weather 24ft light boat with 25hp inboard diesel engine was more than enough. It also used really little fuel. But little bit of wind and waves and it was quite risky to stop the boat for fishing. On 32-36ft and a bit on the heavy side ships could continue fishing in quite a bit worse conditions, rolling could be big and sometimes a scary, but it's slow enough to not fall out or keep balance without too much trouble.

    Here is a link to most common type of fishing boat, used 32ft yamaha ヤマハ DX32G | 船ネットドットコム http://www.funenet.com/content.php?id=5036&nomal
     
  11. Mr Efficiency
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    Mr Efficiency Senior Member

    Is the climate cold and wet ?
     
  12. xellz
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    xellz Junior Member

    Summer hot and humid, winter doesn't drop below zero at all and mostly stays above 10C. Expect typhoon season, it's rather calm with few strong wind days, winter however almost always windy and nasty fast waves.
     
  13. Mr Efficiency
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    Mr Efficiency Senior Member

    Seems to require nothing more than an outboard tiller-steered boat, if it is just one-man line fishing.
     
  14. xellz
    Joined: Jul 2017
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    xellz Junior Member

    Yeah, when it's calm i agree. During summer most likely won't be that many days that have to skip due to weather, rain can be more annoying in small boat, but not a deal breaker. Usually starting from October until next summer windy days are common and in small light boat it's difficult to continue fishing. I actually thought about it quite a lot, if fail with catamaran just get a small boat with 20-30hp engine and do other jobs when weather doesn't allow fishing. At least it's a lot safer option and still will allow me to go out in sea. Now i certainly can't imagine my life without sea. Office job might allow me to earn quite a bit more and with a lot less risk, but i will always feel my time being wasted.
     

  15. Mr Efficiency
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    Mr Efficiency Senior Member

    You might enquire of Richard Woods how his cat handles with one motor when trolling, with the widely spaced hulls you might get a turning effect that is annoying, especially in a joggle. Having to use both motors will send the fuel bill up.
     
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