Discussion in 'Multihulls' started by guzzis3, Mar 18, 2021.

  1. guzzis3
    Joined: Nov 2009
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    guzzis3 Senior Member


    Still blind from my strokes but resuming life again gradually.

    I don't get motion sickness. I did get sick on the tassie ferry but that was the vibrations through the boat from the engines. Still bitter about that trip, truly awful.

    Anyway the boss has indicated she might be up for joining me cruising. She is likely more susceptible to motion sickness. I'm planning on building a catamaran, and I only want to do that once.

    So the question is is a boat with a 30ish foot waterline going to be easier to stomach than one with a 25ish foot waterline ? Will it make much difference ?

    I have plans for a 25' cat but I'm wondering if I should see if I can upgrade then to a 30 footer. Big decision, lots more money and I'll run essentially the same accommodations. Speed is not a consideration, it's a catamaran :D

    I'd only do this for a nicer motion in a seaway. Sailing in queensland. We don't get bad ocean swells due to thin water and the great barrier reef. We do get a lot of short sharp chop. If there are big seas I'll be hiding in port or up a river somewhere...

    Thank you in advance.
  2. TANSL
    Joined: Sep 2011
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    TANSL Senior Member

    Among all the factors that influence the movement of the boat, especially the transverse one, it is perhaps the length that has the least influence. It may be appropriate to consider other factors before the length of the waterplane. Define what degree of comfort you want to achieve, what "comfort" is for you (speed and frequency of movement, range of movement) so that someone can give you a more definitive answer.
  3. oldmulti
    Joined: May 2019
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    oldmulti Senior Member

    Guzzis3. I have spent months sailing in Qld waters on 30 foot tri's, 37 foot, 45 foot and a day on a 84 foot cat. In the reef areas the size did not matter especially if cruising. You choose the weather window and life was good. The real consideration was the accommodation. Headroom at the galley was a must, being able to look out windows while cooking, having somewhere really comfortable to sit out of the sun and wind a must. Big comfortable, well ventilated bunks in a low motion (near central to aft) location really helps. If the boss is experienced in sailing good, if not, a good engine that can easily be deployed and started helps build confidence about cruising. Also enough storage space so that food can be logically stored, sailing gear and other clothing can be stored separately and a supply of musical/e books/audio books to keep you amused. Finally a dingy and anchoring equipment that can be deployed and taken in very quickly for all those odd occasions you need to explore etc. I know designs from 23 foot up (eg Woods Wizard or Sango) that will do most of the above, but if you want to "walk" between the hulls stooped or vertical you will need a cat from about 26 foot. Summary. The smallest boat you can live on the happier you are likely to be, but I already think you know that.

    As seasickness is a personal thing the shape of the hulls on a cat can eg Have fine ends and make a person seasick, others will be OK. I find full end hulls most comfortable for me but other people I sailed with found fine end hulls better. Also after a few weeks on board most (not all) people will adjust to living on board and not be seasick.
  4. fallguy
    Joined: Dec 2016
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    fallguy Senior Member

    It is difficult to top the comments by old multi. The headroom is a biggie.

    The Skoota 28 is a fast build for a wood worker. I think it will meet most of the recommendations above. If you want to sail, Richard has a few other designs. You will want to get the headroom I'd say. The Wood's Gypsy is the least I'd go with for sailing.

    At some point all recreational boats become 'small' in 'big' seas. Anything much over 6 foot waves becomes far less than fun; especially if they are coming fast. And the job of the captain on a recreational boat is the safety and comfort of the crew.

    I like the 28 size in ply for balancing build speed and accomodation. If you have more build time and more labor to support the build; you can go bigger.
    Will Gilmore likes this.
  5. redreuben
    Joined: Jan 2009
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    Location: South Lake Western Australia

    redreuben redreuben

    I'm not a sea sickness person so just my 2c worth to increase your sample size, I used to crew on 40's IOR mono's offshore so have seen rough water we used to regularly sail with hangovers and get by with a few quick eze. Plenty of people get sick on monos ok well known fact, the rolling downwind seems to induce more than the pounding upwind.
    The next worse boat is the catamaran upwind when the boat gets that jerky squirmy hull walking shudder when waves are hitting opposite corners.
    The most comfortable boat sailing is the trimaran, it has the beam and it just leans into the float buoyancy and glides (slight exaggeration) along uphill and down, at anchor however different story, depends on the load/float dihedral but the slap slap from one to the other can be infuriating, racers more so than cruisers, of which I have no experience, if the floats touch the water its probably little different than a cat but of course without the payload a cruiser needs.
    Therefore the way I read your needs, stick with the catamaran you like and avoid windward work or go with longer and thinner hulls with the same rig.
  6. guzzis3
    Joined: Nov 2009
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    guzzis3 Senior Member

    Thank you for the responses.

    I'm not concerned about the other matters. I think I have them well in hand. Me alone on the boat a 25' is plenty. Truth is wizard or similar would do except it doesn't offer the headroom in the hulls I want even with the clip on cabins, and fitting a head to the rotating hulls is problematic. The boss won't come at a porta potty.

    Then is to build wizzer with a bridgedeck cabin like sango, but with headroom, demountable not folding. I'm not planning on going too far from land, and running at any sign of bad weather. No timetables, no rushing. Always able to wait out bad conditions.

    I have looked at tris. The avalon 9 in foam with the scarab 32 style beam mounts (and centerboard) would be good, but I can't see a way to get a proper double bed. Accommodation is always the problem with tris. They also require more materials than cats for the same load carrying capacity. They do have their advantages though. Maybe a 30' tri would be more comfortable than a 25' cat for her to sleep aboard ? Dunno.
  7. Will Gilmore
    Joined: Aug 2017
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    Location: Littleton, nh

    Will Gilmore Senior Member

    Guzzis3, I grew up around a range of boats. My father ran 65' catamaran headboats out in the Gulf of Mexico, my family lived aboard a skinny 56' monohull schooner, I sailed a hobie 18 on a trailer for years before my wife and I settled down to have a family. I've crossed the Atlantic with my wife and parents aboard a Shannon 50 and seen friends and passengers and family sea sick and been there myself. The best thing you can do for your wife is give her the bigger boat, but it has nothing to do with sea sickness. Have her take Meklazine.

    She will simply be happier with more room, all other considerations being trivial.

  8. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Those anti-histamine meds do work, but can have side effects, and care is needed if there are medical issues of certain types, so read the instructions carefully.
    Will Gilmore likes this.
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