Wharram Hitia 17 questions

Discussion in 'Multihulls' started by Onefish, Oct 24, 2019.

  1. Onefish
    Joined: Oct 2019
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    Location: Pennsylvania

    Onefish Junior Member

    Hi, I'm looking into a few options for a build and one of those possibilities is a Wharram Hitia 17 beach cat. I love the aesthetics and reputation of James Wharram's designs, but I would like to make a couple modifications.

    One is that I was thinking of strip planking it in stead of doing stitch and glue, I understand it would take longer to build, but I think it would be cheaper and easier to get the necessary materials(1-by lumber of any given species is easier to come by than marine ply of any given species).

    Second is the forward most cross-beam. I have heard this can cause problems in choppy conditions when going over a wave it will slam into the water and slow things down. I was wondering if anyone can corroborate this and if so the options to deal with that. I was thinking of either moving it back a couple feet or maybe getting rid of it while reinforcing the other two cross beams to compensate. Would modifying the forward cross-beam to cut through the water better be an adequate solution?

    Third is the most complicated. I was thinking of putting a more powerful rig on it. I was thinking something like a 24-26 foot wingmast setup or maybe a rig from a hobie 16. I understand that James Wharram overengineered his designs to a degree in the interest of stability and reliability, so I am wondering if such a modification would be within design tolerances still or would require additional modifications such as stronger cross beams or possibly reinforcing the spots on the amas where they are attached, or maybe added strength where the shrouds attach to the hulls? Also, would the skegs need to be modified to account for the change in the sail plan? All of the above?

    Any help would be greatly be appreciated. Thanks.
     
  2. gonzo
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    gonzo Senior Member

    The modifications you propose are structural, and require re-engineering the design. Basically, you want a different boat than a Wharram. It is possible, but expensive to pay for a new design. Further, if you keep the same lines, which James Wharram owns, there will be a royalty fee.
     
  3. bajansailor
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    bajansailor Marine Surveyor

    If you are passionate about building in strip planking, then choose a design that suits this method, such as a cat with round bilge hulls.
    The lumber might be cheaper than the marine plywood initially, but I think you would probably need a lot more epoxy and glass (and time and effort) with strip planking compared to plywood, which would rather cancel out this cost difference.
    As Gonzo says, it does sound like a different boat would be better for you, re how you want to change the Hitia so much.

    Have you had a look at Richard Woods' designs?
    His Wizard can have strip planked hulls -
    Sailing Catamarans - Wizard - 6.6m folding trailable cat with central cuddy http://sailingcatamarans.com/index.php/designs-2/2-catamarans-under-25ft/161-wizard

    Re your query about using a rig from a Hobie 16, the website mentions that the 21' Acorn can use parts from large beach cats (minimum size being the Hobie 18).
    Sailing Catamarans - Acorn - 6.4m simple 2 berth trailable hard chine hulls http://sailingcatamarans.com/index.php/designs-2/2-catamarans-under-25ft/167-acorn
     
  4. guzzis3
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    guzzis3 Senior Member

    Don't build a wharram they are awful and his plans prices are outrageous.

    If you want something stylish either get Gary Dierkings outrigger sailing canoes and build a catamaran from that, you could use ulua if you want strip planking...

    or get selway fishers hawke plans Small Catamaran Dayboats http://www.selway-fisher.com/Smallcat.htm. It is stitch and glue but it's a really nice boat.
     
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  5. Onefish
    Joined: Oct 2019
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    Location: Pennsylvania

    Onefish Junior Member

    Thanks for the responses everybody.


    I have seen the multihulls on Selway Fisher and they didnt quite appeal to me. My other two options I was considering were a Woods Quattro 16 and a W17. I really liked the aesthetics on the Wharram designs, but i felt that the Hitia 17 was so wet that I might as well get as much speed out of it as I can. If it's too impractical, then I guess that eliminates that option.

    I took a look at Gary Dierking's designs on your suggestion and they do intrigue me, the T2 in particular. I must ask though, what makes turning one of his proas into a catamaran less complicated than my aforementioned modifications to a Hitia 17?
     
  6. gonzo
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    gonzo Senior Member

    Any 17 foot cat is going to be wet.
     
  7. Onefish
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    Onefish Junior Member

    Okay, so can you clarify a bit? I really only expressed interest in doing two modifications and more or less simply wanted to know if any of the others were necessary. Are you saying all of them would be?

    So, are you saying that I cannot modify the sail plan or construction method of the design without James Wharram's permission? Because I've seen multiple examples of people using something other than the sprit and wing rigs he designed his boats with. Also, strip planking is just something I would like to do, not really something I have my heart set on.
     
  8. Onefish
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    Onefish Junior Member

    Actually, I am curious what your criticisms of Wharram's designs are? I'm not arguing, I would genuinely like to know. I agree with the pricing, I think they are pricier than everybody else out there.
     
  9. gonzo
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    gonzo Senior Member

    You want more speed, and increasing sail area to achieve it. That means that the whole structure needs to be designed for the increased forces/stresses.
     
  10. TANSL
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    TANSL Senior Member

    Not necessarily. We should see what speed increase we are talking about. In motorboats speed is a determining factor while in sailboats it is not.
     
  11. guzzis3
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    guzzis3 Senior Member

    Excellent question.

    First I have not seen Wharram's Hitia 17 plans but I have seen tiki 21, 30 and tanenui plans. His approach to building is horrific. Incredible waste of materials and time. If you look back through this forum there was a long discussion (started by me) about the tiki 21 where we discuss some of the specific problems with it. Building a Wharram takes twice as long and twice as much money as it should. And that doesn't even cover how ordinary the result is.

    Regarding your modifications unless you are planning to strip plank flat panels and assemble them to the origional shape you are essentially redesigning the hulls, so why not start with a round bottom hull designed for strip anyway ? Increased rig wants more than anything wider beam, so you will be ditching the Wharram beam design for something a bit stronger. So now you are no longer using Wharram's hulls beams or rig. So you've bought plans for how much ? Why did you do that ?

    Gary's book can be had for whatever it is $30 or something. Everything you need to build 2 strip hull types which would work nicely as cat hulls.

    Design your own beams. If you can tell us what rig you want someone here can tell you what you need and really easy options to build them depending on your preferences.

    Gary's book has fantastic details on building rudders and leeboards. His beams are a bit light for what you want but as I say easy fixed.

    Wharrams are wet. If this bothers you just build the GD hulls higher. He also gives details for double outriggers. I know you want a cat (I love cats) but you can build Ulua 26' long with double outriggers. Easily demountable, easily paddled or motored and all the rig options are there in his book. Just another option.

    Overall for what you want to do it would be easier and cheaper than starting with a Wharram design.

    Did you look specifically at Hawke ? I agree SF's boats are mostly uninspiring but Hawke is special to my eye...

    No matter what you end up building I recommend GD's book anyway. Seriously every year of 2 I pull it out and reread it. Fantastic book.
     
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  12. Onefish
    Joined: Oct 2019
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    Onefish Junior Member

    This has been an incredibly helpful post. Thank you very much.

    So, a little more info on my situation. I am limited by my workspace to a length of about 18 feet at the absolute most. I could do 18.5 but practically speaking 18 is just more practical to work with.

    I have been looking for one of two experiences. Either a boat that is fast yet wet, or a boat that is dry/comfortable and more leisurely. That being said, there is something to be said for aesthetics, which is where the Hitia 17 comes in.

    I'm not set on going with the Hitia, I just was looking into my options. The strip planking is not something i absolutely have to do, but I think it would produce a rewarding result.

    I am definitely going to pick up Dierking's book. If I do decide to go with one of his, I was toying with the idea of something with a canting mast like the Gibbons rig on the T2. I dont have the time now, but tomorrow or the day after, I can put up something illustrating what I was thinking about.

    The Hawke is interesting, I may consider it.

    Again, thanks for your help.
     
  13. guzzis3
    Joined: Nov 2009
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    guzzis3 Senior Member

    GD gives details on how to build waapa in 8' sections. You could do the same with ulua. 2 piece hulls bolts together. Simple. Ulua is 18' normally so you could build an 18' cat based on it, but if you want to go longer you can build in 2 sections.

    Please understand I am not telling you what to do. I obviously don't know all the details of your situation and preferences. I am trying to give you options.

    GD is remarkably agnostic. He shows you in the book how to mix and match different design elements to build your own version of the boats. You an take a float from one, beams from another hull(s) and rig then build a single outrigger or double. He doesn't talk about cats but it's not hard to go there. He details leeboards which are much better than relying on V hulls for leeway, offset rudders, motor mounts etc. The book is beautifully written and you will learn a lot no matter who you are.

    And the boats are beautiful. Waapa maybe not so much but it's a "practical" build. To each their own.

    Do shop around as prices vary a lot and of course depend on where you are in the world.
     

  14. Onefish
    Joined: Oct 2019
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    Location: Pennsylvania

    Onefish Junior Member

    Here is something I threw together to give a rough approximation of the rig I was thinking of. It's not to scale or anything, but it shows what I have in mind.
     

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