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 Senior Member

    I did speak with him and got lots of useful information. That's one of reasons why i got so fixated on catamaran. One engine cruising appears to be quite good and their Skoota 28, live aboard power cat, with 2 ppl can cruise at about 7knots on one 20hp engine at 3500rpm. But with catamaran my main goal is electric propulsion, won't be using outboards for too long. With electric there is no issue using both engines at any speed. Thanks, having a conversation here does help to relax and collect my thoughts on this matter :)
     
  2. Mr Efficiency
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    Mr Efficiency Senior Member

    So no steering effect with a single engine, when pitching ? Good if you could get that, I just thought the wide spacing is against it.
     
  3. xellz
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    xellz Senior Member

    I don't think it's possible to make zero steering effect on one engine with such a wide beam, but seems it won't be that apparent. Wide beam should be great for drift fishing and help fuel efficiency.
     
  4. Mr Efficiency
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    Mr Efficiency Senior Member

    You won't get it in smooth water, just when the underwater profile alters in choppy water, if you are trolling several lines can cause a tangle, but I guess the lines are further apart anyway.
     
  5. Rumars
    Joined: Mar 2013
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    Rumars Senior Member

    Xellz I was away, sorry to hear about your problems. No take a deep breath and think about overcoming bureaucracy by design. For example you could build something like a philippine paraw, one slim long hull with low buoyancy outriggers. Make the outriggers fold and declare them "retractable rough sea stabilizers". No mention of anything trimaran-ish or multihull-ish to the autorities. And since the outriggers are so thin they can not be seen as a hull (in most paraws it's just a bamboo pole). If you want trampolines between the beams you declare it "safety device for preventing man-over-board accidents" and say they are necessary for singlehanding fishers. The drawings you present will all show an unusually slender monohull and in port you keep the things retracted so any inspectors passing by only see a monohull. Many fishing boats use stabilizers and outrigger booms so nothing unusual about yours except the shape. If you want you can also add a "stabilizing sail" to make the package complete.
    Of course it would have to be a custom design. Such a craft would probably be cheaper to build compared to a catamaran.
     
  6. fallguy
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    fallguy Senior Member

    The limits for line fishing alone are waves 2-4' in any monohull. It is simply impossible to keep the boat on course and operate lines in any conditions greater. Trust me, I know. Waves 2-4 are very difficult. Does some guy in another country do it? Sure. Is it easy. No. Safe. No.

    The limits for line fishing in the Skoota series or any catamaran will be greater, but 3-6 is probably a maximum. The fanciful Deadliest Catch with the boats running pots in 5+M seas is just that; fanciful.

    The benefit with the Skoota series is you will be able to take a few more risks and keep a 2nd person on the lines in rougher seas and not worry about running head or following so darn much. Trolling in a monohull in a beam sea just sucks. Again, do people do it. Sure. Does it suck. Yes. Instead they accommodate and run head and following and then vary course, avoiding proper course, etc.

    Show those Japanese fellows a picture of the Skoota 28 on the water. The Jazz is the same boat 2' longer.

    The capsize wave height of most hulls is the beam. For a 10' monohull; 10' waves, and for the Jazz; 16' waves. Corrections and debate are welcome on the monohull, but the Jazz numbers are from the designer. (personally, I'd not want to be in a 6' beam sea in a 10' wide monohull, but that's just me)
     
  7. fallguy
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    fallguy Senior Member

    Also; if you ask Richard in a month or two; he might be willing to give you the hydrostatics of the Jazz for a downpayment on the Jazz plans. ? Put the hydrostatics and an article from an NA on multihull capsizing in front of the overseers.

    He is very busy now.
     
  8. xellz
    Joined: Jul 2017
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    xellz Senior Member

    For foreigners there are lots of limitations, i wasn't aware about quite large portion of those limitations, especially when it comes to commercial use. Registering my wife as owner will remove lots of headache, no need for a license to be owner of a boat. But at some point i thought anyway of changing my nationality, the process though is a pain. I've been out on various fishing vessels by now and it made me want a catamaran even more. For example to go from stern to bow, you will have to pass 20-30cm narrow path, strong rolling during drifting in anything but calm waters etc. Designing new boat is overkill and i don't have such resources right now. So it's either one of used boats available for sale at low price or catamaran. With used boat i will have to give up electric propulsion completely, with Jazz 30 i still can convert it. And i already bought the plans, so...
     
  9. xellz
    Joined: Jul 2017
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    xellz Senior Member

    Since last post about everyone i spoke to was again't using catamaran too, they have strong image that it's only calm water boat and is not suited for fishing. Also price always appeared as argument against catamaran, sure it will be more expensive than 30yr+ old fishing monohull with same age engine, no surprise here. But somehow most people refused to believe that catamaran designed for efficiency and build from lighter material can save quite a bit in fuel cost in expected 100-150 days of active use per year. My point about customers likely to rent out new, more safe boat, than old, exact same as everywhere else also gives no effect either. Just recently one of fishermen had to be dragged back home because his engine died, luckily it was close and phone worked still, didn't turn into major accident, but surely 2 engines are better than one. And here my stubbornness kicks in and i want to actually follow through this project even more. Although i'm completely on my own now, no usual subsidies that fishermen receive in remote places, however small they are. Even build location now is under question and i'm already starting to prepare to build my own shed.

    I'm certainly not expecting miracles here and won't be trying to repeat stunts similar to Deadliest Catch, but from what i learnt and saw from videos, i can expect more comfortable and safer environment compared to similar length mono. Deck space alone is huge benefit, moving from stern to bow will require to pass 20-30cm wide path. When boat rolling strongly it's not exactly fun. Live bait, cooler boxes are in front of pilot house, fishing rods behind. Need to see fish-finder well. That's the usual setup for local 24-32ft fishing boats. And what you wrote fits here really well 'do people do it. Sure. Does it suck. Yes.'

    I've bought plans for Jazz 30 a while ago already. Most likely going to start after rainy season, to avoid exposing non-sealed material to over 95% humidity. I.e. summer. But before that i need to clear last questions, the process of registration of self-build boat for commercial use and epoxy importing is still not certain.
     
  10. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Being almost local, i'd be happy to assist..

    Aahhh..but sounds like you have it covered now though..
     

  11. Rumars
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    Rumars Senior Member

    Xellz I wish you luck to realize your dream. It's sad there are so many obstacles, but I hope you will prevail.
     
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