Need Advice with Houseboat Construction

Discussion in 'Boat Design' started by SNGPSo, Feb 4, 2021.

  1. fallguy
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    fallguy Senior Member

    A lot of people don't account for rotation of the transverse beams properly. Here, no different.

    Stop for a moment and explain the purpose in making a temp lashing like a Wharram cat for a stiff houseboat.

    I have read a wharram cat can move 5- an unheard of 15cm with her lashing system. You can't make that work here.

    Then explain what will keep the transverse beam from playing dominos.

    Addendum: so noted a groove for the transverse/floor joists.

    As bajan I believe mentions, why not glass tab the joists to tbe hulls?
     
  2. SNGPSo
    Joined: Feb 2021
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    SNGPSo Junior Member

    Thank you for your suggestions guys. This is a personal project that I am having creative fun with, but I am still looking for a local designer who can help me fine-tune the details of the plan. If anyone is interested in working with me please feel free to PM me.

    upload_2021-7-2_7-53-13.png

    The word ''dubious'' was stuck in my mind for a while, bajansailor, haha. The idea of glassing the whole bottom (Orange) was hovering in my mind since, so I am glad you suggested glassing the beams later on as well. I think adding triangular steel brackets, between longitudinal and transversal floor joists, is not necessary to add stiffness anymore now that I am glassing the whole bottom. I also thought about 'merging' the beams and pontoons in 1 structural composition (Green). The only thing still nagging at me is how to have a secure connection here (Blue Diamonds).

    What do you guys think?

    Another view:
    upload_2021-7-2_7-58-7.png

    Thanks!
     

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  3. fallguy
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    fallguy Senior Member

    I glassed the bottom of my catamaran cabin on a table, rightside up. I used plascore which came in 5'x10' panels. The plascore can fool an amateur and you may not use enough resin to wetout the veil. This is a dubious error. This is a thirsty core and I'd say about 110-115% of glass weight is needed. I wetted the veil as fast as humanly possible to avoid it seeping down. The best way is to wet a roller like paint and run it dry. Otherwise, the honeycomb fills.

    Then the seams are bonded. Plascore has a big downside. The edges cannot be left raw and must be buried.

    You seem to be missing a basic concept of fiberglass work which is tabbing.

    The floor joists can be tabbed to the toons just like a stringer is bonded to a hull...with fiberglass tapes. You can use epoxy for a stronger joint, but not needed if you have lotsa floor joists.

    The rim joists would also be bonded to the floor joists same way. First screw them, then remove the screws and add bonding putty and then tab each one.

    Have you resolved issues like freeboard? You don't want water seeping up onto the cabin sole, so you need some minimum height. I am not sure what that is, but 12" seems low and 1/2 meter seems like plenty?

    If you used plywood, you could glass the down side, then screw and bond it up onto the joists, then tab the seams. The only way to escape working upaide down here is to flip it after the joists are bonded and tabbed and the rims are on so you don't domino.
     
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  4. TANSL
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    TANSL Senior Member

    @SNGPSo,
    I believe, and allow me to tell you with great respect, that you are making many mistakes but two are very important:
    - You have neglected to know if it is going to float and if it will float correctly and to ensure the necessary safety conditions for an artifact that is going to house passengers.
    - You have been determined to provide constructive solutions and that is an area in which you are showing that you do not have sufficient knowledge.
    I do not mean to offend you, do not take my words wrong, I only intend, and I have been trying for a long time, to help you.
    I repeat once again, write the SOR for your houseboat yourself and let the experts do everything else.
     
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  5. SNGPSo
    Joined: Feb 2021
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    SNGPSo Junior Member

    No need to worry, TANSL. I have actively looking for an NA to help me with the job. I appreciate your honest feedback. My work on the plan is a sort of SOR in itself, since it clearly defines what I want. It outlines how I want the boat to be like, and the professionals can take it from there.

    Thanks for the feedback, fallguy. Yes, I did take into account the freeboard calculations, but I will also let the NA double-check everything I did. All I need is to find one now, hahah.
     
    Last edited: Jul 3, 2021
  6. Ad Hoc
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    Ad Hoc Naval Architect

    Im curious.
    If you will find/use a NA, what is the purpose of doing all this work and posting it too?
    The NA, whomever you choose, will tell you what is right and wrong within a simple 5min chat and most likely render you 'musing' all moot. So why waste time cogitating when a simple 5min chat with your eventual NA will sort it all out for you anyway?
     
  7. TANSL
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    TANSL Senior Member

    A SOR must include things like, for example:
    • General Arrangement plan, which is the only thing that could be assimilated to the renders you have presented, but which lack many details that a GA includes.
    • Definition of the vessel
      • Vessel Type
      • Approximate main dimensions, if there are any limitations.
      • General description
      • Tests and sea trials
    • Constructive system, if there is any limitation or preference in this matter.
    • Regulations that the device must comply with.
      • Classification Society or similar
      • SOLAS
      • Marpol
      • Colreg
      • Radio and communications
      • ......
    • Navigation area.
    • Design category.
    • Type of propulsion
    • Desired speed.
    • Autonomy.
    • Materials for the various elements and workmanship.
    • Equipment and out fittings.
    • Auxiliary systems
    • Special loading conditions, if any.
    It is not an exhaustive list, the only thing that is intended is to make you reflect on whether the information presented in your beautiful renders is enough.
    The first thing you should know is that without the above, no serious NA will waste time making any calculations or estimates, nor will anyone be able to tell you if your house boat is correct or not. A project, be it a boat or whatever, is correct if it complies with the SOR (a complete and correctly made SOR). The better it fulfills the SOR, the better the project will be.
    Once the SOR is written, you will surely find help more easily.
     
  8. SNGPSo
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    SNGPSo Junior Member

    Ad Hoc, I know what you mean, but I am just enjoying the creativity of it all until I eventually find the NA.

    TANSL, I think I mentioned before that this houseboat is motorless, which not only considerably simplifies the SOR itself, but also the construction and permits.
     
  9. TANSL
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    TANSL Senior Member

    In what sense and how, what are those permits? All this is very important to be able to hepl in your project.
     
  10. SNGPSo
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    SNGPSo Junior Member

    They are needed to give a sort of license plate to the houseboat, even if it's motorless and is standing still.
     
  11. BlueBell
    Joined: May 2017
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    BlueBell "Whatever..."

    "Need Advice with Houseboat Construction"
    I've been following this thread off and on and it's only making less sense the farther it gets.
    My advice is find a design you like and caters to your Statement Of Requirements.
    Do not design it yourself.
    Good luck.
     
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  12. TANSL
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    TANSL Senior Member

    @BlueBell, I agree with you on everything, but since SNGPSo does not have SOR, it is not possible for him to find anything that suits it.
    He is still committed to his renderings without realizing that they, without more, are not good for much, only for when he wants to make his publicity brochures to sell the house boat.
     
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  13. SNGPSo
    Joined: Feb 2021
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    SNGPSo Junior Member

    Just to clarify everything; I am not refusing help. I am actually actively looking for it. As I stated before, everyone I spoke to in person was not able to provide assistance, stating that they never built houseboats before, only boats. I also looked relentlessly online for professional help, as some already know, but was unable to receive it. Now I know where to look to get help, so thank you TANSL for guiding me to that.

    I thought the forum was a place to share knowledge and provide some assistance, even to amateurs like me who are interested in knowing more about the craft of boat building. I stated before that my approach to this project to this point is almost purely creative thinking until I am able to find professional help.

    I will stop posting from here on out since it seems to rub people the wrong way. Thank you to everyone who was kind enough to provide help and engage in conversation.
     
  14. Boat Design Net Moderator
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    Boat Design Net Moderator Moderator

    Just wanted to interject here as I didn’t want you to feel that you rubbed people the wrong way. It’s important that the site is a place where people can learn and ask questions to pursue their dreams. Posting early concepts and getting direction on something new is fine. At the same time we are lucky to have Naval Architects and engineers who are willing to share their experience. Sometimes the responses are warnings to try and keep someone from being disappointed by skipping a step or going in a direction that the responder feels is potentially fraught with danger. Or a recommendation that professional work is needed for the complexity of the question and project at this stage. Just wanted to interject here as sometimes there is a disconnect between people asking questions and members trying to offer their best assistance. I don’t want to see people feel that they are unwelcome to ask a question or share a project in progress, as these are certainly welcome.

    Reviewing this thread from the beginning to the end, I think there was concern because in the forum thread it went from conceptual, to how to calculate preliminary weights and displacement, and then there was a big gap, and then specific questions about connections.

    I believe in the first post you stated you were an intern architect (land based); think of the SOR (“statement of requirements”) as you would think of the “program” for a building: what are the functional requirements and goals that must be achieved to be successful, what are the durability requirements, what are the code requirements, what are the safety requirements, and so on. Tansl and some other members have English as a second language and so sometimes their comments can come across as snarky when they may not intend them to be so in English. Also you may read BlueBell’s comment as dismissive, but I do not believe he meant it in this manner. With a land based design, before designing something new, you would first understand details of conventional builds, through studying existing buildings and standard details. Thus his comment that a first approach is to see if any existing houseboat plans meet your design requirements. If not, can an existing, proven design be adapted to meet your layout and style goals while utilizing proven details. And if neither of those, then with that knowledge, design something for your unique requirements.

    In any case, just wanted to interject. Most members really do try and offer their input and experience in a way that will be helpful. Hope you have gotten some direction and input to consider, at least in the conceptual phase, as you undertake a new endeavor, and very much hope you are successful with your overall project.
     

  15. bajansailor
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    bajansailor Marine Surveyor

    @Boat Design Net Moderator - that is an absolutely brilliant summary above! Thank you for taking the time and care to write it.

    @SNGPSo - please be assured that everybody on here wants you to succeed - equally, if they see you doing something that seems rather foolish, they will not hesitate to point this out.
    There are lots of existing houseboat designs available online - I am not aware of any that have lashing systems like what you proposed earlier - and that should be a warning signal already. If it was a good way of building a houseboat, somebody would have done it already.
    Try and find something that seems reasonably close to your requirements, and then the good folk on here should be able to help you to do the rest if any design changes are required.
     
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