Trimaran Design Concept with longer foils than the main hull

boraicus, as a newcomer to boats myself, I'm enjoying your thread. As you can see, this forum is quite special, in that you are getting responses, input and advice from world-class experts with decades of experience, who are also generous and enjoy helping out. I would not be able to estimate the hourly rate you would pay if you assembled these same people in a room together for the purposes of answering your questions $$$ (Let's not even include travel, hotel and per-diem expenditures)

I want to respectfully suggest that the response, summarized by Ad Hoc's SoR mantra, and fleshed out by Richard Woods' post, is different than what I highlighted in your post. Though important, your quest for 'knowledge in general' is not as valuable as you presume because it does not necessarily result in a cohesive conceptual foundation of understanding which somehow enables you to then begin specific, nautical problem solving. Knowing how to create a hull with a particular mathematical function doesn't teach us directly what hull shape best satisfies a particular usage.

Yes, you can continue to study and learn, then come here and post more questions about particular technical things, but the suggestion is to focus and specify a particular functionality, which through an iterative process, narrows, not widens, specific, possible technical design solutions to what you are trying to achieve.

For example, let's say you wanted to design a boat very much like Richard Woods' "Banshee", and what it accomplished in function, but did not have it as a particular finished design example to learn from directly. Imagine what you would need to specify, learn and understand to achieve this. Fundamentally, you would need to acquire at least a basic understanding of hydrostatics and hydrodynamics. Then, just the questions alone that you would present to forum collective as you began your design spiral would teach you a great deal. The means by which you achieve this end would give you a tremendous boost in knowledge.

 

Generosity

Tomas, you are quite right, and I am greatly indebted to everyone's generosity. This a great place for amateurs and professionals to meet and I am humbled by the time that people take to share their feedback with me, and very grateful. If not for the generosity of the people on this forum, I probably would never have developed such a keen interest to learn about boat building and design.

Thanks to everyone again for all of your input!

I agree. I think perhaps I am not a great communicator. I wanted to convey to everyone my realization that it would most likely be more beneficial to me to study than to ask questions. This is probably a better place for me, now that I am learning more about design, albeit very slowly, to simply share what I little I am accumulating and piecing together, than to ask questions. I believe that is what I was trying to convey in my last post, but I probably did not do that very well, and I apologize! Unfortunately, I am not as great about communicating over text as I am as communicating in person. I am by nature very long winded - so I don't know that that improves things with respect to my style of communication - but I believe am better able to convey my sense of gratitude.

It is quite difficult to be both technical and communicate in a way that shows appreciation, and much is left to unfortunate misinterpretation. Sometimes I wonder if I could state things better than I did, and yet I don't know how, a lot of times to convey the content of what I am trying to convey until I see someone reply to me. :/ I hope I have shown my appreciation to everyone and that people know how grateful I am for their input, their advice, and their time.

I don't always know always know how to respond beyond "thanks very much," etc, etc. What I mean is that the problem with my communication is when it comes down to trying to both convey and understand the meat of what is being discussed.

For instance, I don't know what I am supposed to do when it is suggested to me to design by an SOR. That is why I replied to Richard and thanked him because he helped me to flesh out something that I had started. But in actuality, I still don't know what to do with it.

Naturally, I concluded that the only meaningful thing I can do is to become more like someone who *would* know what to do with and SOR, and my response was essentially - yes, I think I get it, guys - I really need to pay my dues here and study up. Perhaps I misunderstood something quite critical? I don't know but I appreciate everyone trying to help me, and please excuse me if I seem too aloof when I am trying to communicate something more technical. Although I have learned throughout the years to be more tactful when communicating, I often still don't know how to best treat a subject except to express what I am thinking and hope that it doesn't come across in a awkward manner. :/

Tomas, thanks. That is a cool idea. I feel at this level, however, that there is still way too much to learn for me before I could even consider approaching such a tack. This is why I believe I should probably stop asking questions, and begin reading. I believe that in a way, I actually am invested in the process that you suggested. For instance, I have discerned the need for a good foundation in hydrostatics, and am proceeding to learn that, as well as proceeding to learn something more about the mathematics involved in the hull design stage. There is definitely plenty for me to learn here!!! I am a theory-minded person. When I was in college, studying political science, I took almost entirely theory classes, except for what was required otherwise; when I was a music composition major, I also excelled at the theory aspect of things. I also caught a lot of criticism for being a student of theory. There are many criticisms and stereotypes of theorists that I have fallen victim to in my time in academia, such as "theorists never do anything," "theory is a just a bunch of hogwash," "oh, no, another theorist," "that will get you a job flipping burgers somewhere," ad nauseum. But really, it is just another way of thinking that I don't think I could change even if I truly wanted to. After so many years you begin to see your flaws and your strengths and to understand how to live with them a little better than when you were initially starting out in life. I don't know that my ability to communicate with others has improved all that much, but I am more comfortable being me, and for what it's worth I think that helps me get along with everyone else a little better too - I HOPE!!

So, yeah, the term "design spiral" actually makes sense to me, because in essence that is what you are doing. A spider doesn't spin a web by completing the right section and then completing the left, he/she lays a few strands and then goes around in a spiral, connecting all the strands that had been laid out cross-wise. I am going around in quite a similar fashion, learning a little here, a little there, coming back around to where I thought I had learned something and developing it more deeply, round and round I go. Granted, my process may be a bit strange, a bit naive, rather clumsy, embarrassing, and possibly even seeming presumptuous at times, but this is just the way I have learned to learn, and I don't think I can learn a better way than the way that comes most naturally. Throw me in. I'll either sink or swim. Forgive me if I splash about while I try to swim!

Thanks again, everyone! I just got one of the books that I had ordered, but after I received it, I realized that I needed something that goes deeper, and I may need to find a general text book on naval architecture instead of trying to find the perfect book for trimaran and catamaran design.

Please forgive me my poor communication skill (or understanding skill) and please know that I am indebted and grateful to you all and I will focus more on reading rather than trying to discuss things about which I am not very experienced (except maybe about things I am sharing that I am learning? -if that is ok with you guys?)

Thanks!!!

 

boradicus, I do not think there's anything wrong with your communication. It's very clear that you are appreciative.

The banshee was just a hypothetical suggestion.

When you say that you do not know what to do regarding the SoR, does this mean that you have no idea what kind of boat you would like to design or build? Perhaps you only have an academic interest in boat design. It seems that the books which you have ordered is a good starting place.

I have found reading the numerous build and design threads, recent and old, to be very helpful and informative. Perhaps that will help you to clarify what you want to focus on.

There is no need for further apologies, just enjoy exploring the forum.

 

Academic Interest

Tomas - my interest is academic at a particular level, but that does not mean that I don't like working on projects either. When I say that I don't know what to do with an SOR, I mean that taking the SOR that Richard helped flesh out some for me, that I really don't know what I am expected to do! I actually thought I was doing what was expected, but it occurs to me that I must not understand at all what is expected, and that the only way for me to learn what I am not doing that I am supposed to be doing is to learn what others know until it begins to make better sense to me what they are talking about.

This is the hard thing for me. For instance, just last night I was watching some videos on Bezier curves and Splines. Now, I had no idea that a B-Spline was so closely related to a Bezier when I was talking about using Bezier curves to make up all the curves transverse to the hull shape. I just "theorized" it would be a cool next step to be able to do! But, I think what I am learning is telling me that B-Splines are what I need, not Bezier curves, in order to do this. Tom Speer had mentioned Splines in his post and in his article. But I did not really understand anything about Splines, and in fact was rather intimidated by the sound of it all. I thought maybe I could try to approach the math of shaping the transverse section of the hull in a simple way that I could understand first and go from that starting point and learn more. But what I am learning is that a B-Spline is actually sort of (from my perspective) a way of connecting Bezier curves together, and that in essence is what I wanted to do, but I actually had no idea what it was called, and had no idea that that was what Tom was talking about in his article - until, I actually started digging deeper so that I could begin to comprehend things in my clumsy, and actually very embarrassing kind of way. I feel like an idiot. But, I am willing to feel like an idiot if I am able to learn, and that is one reason that I am so grateful to people on the forum, because of their kindness to me!!!

Theorists are a bit strange, and that in itself is quite embarrassing to me. Because I grasp certain things on a theory level, it may sound like I understand something more than I actually do because of the way in which I describe my intuition about things.

There are many levels at which I approach things. Do I plan to approach things from several different levels - no, it happens as a part of my process for learning things and being interested in things, but it can also figure into the decision process about whether I think something is even practical or not - just like with boat building. For example, I might be quite interested in math as it relates to a project for a while because I think it is cool what you can do with math, and it comes in handy in other areas - not because it is even practical, but because it is fun!

 

So... tell me the truth someone - please... I was initially well received here and I was enjoying sharing ideas with people - but now, without any explanation that makes sense, people who were originally so encouraging to me, are not only no longer encouraging, but actually respond with inexplicable revulsion toward me here on the forum. It's sort of like when someone makes up a mean nasty story about you and no one is willing to tell you what it is all about.

I would really like to know what it's about.

I just want to be able to share what I am working on with the curves - I know there are other beginners on the forum besides me - so why the flack? Why am I being persecuted for learning when everyone else here is doing the same thing?

BTW, (this part to Tomas I don't appreciate being pigeonholed as an "academic." Sure, I used your term to try to explain how I work and think through things - but on a forum about building design, it is rather insulting. The term in the context of boat building implies that I am a nerd - not a sailor. I may not be as an experienced sailor as everyone else is here, but I grew up in Florida and have been out on boats all my life. If you are going to insult me, feel free to be blunt about it - who knows, you might even earn some respect. At the least, your opinions will be out in the open where they will be discussed.

In any case, I may not feel encouraged at the moment, but I am not deterred, and will share what I can with others, and I hope it will be helpful.

Thanks.

 

I didn't think anyone was responding with "inexplicable revulsion". Not like some threads and posters!

But I would suggest you shorten your posts, otherwise they take too long to read

There is a lot to learn. Remember we went to college full time for three years to learn the basics of yacht design/naval architecture. After we qualified we quickly realised we actually still knew very little. As is the case in every discipline of course

Richard Woods

 

Richard, thanks again. There is a lot to learn, and it is quite humbling. Thank you for your encouragement!!!

 

All three of those were simply my classification of different styles of topsides. They all had identical shapes below the waterline. I was aiming to come up with a set of parameters that were flexible enough to use for both the main hull and the ama of a trimaran by just changing the values of the parameters.

The conventional shape had rounded gunwales and was typical of ama shapes. Rounding the gunwales reduces the aerodynamic drag. The flared shape was typical of hulls that have a sharp corner at the gunwale. The bell shape was typical of a multihull main hull that was flared out above the waterline to provide space for accommodations while still having a narrow hull in the water. This would be typical of many designers - Shuttleworth, Farrier, Hughes, White, etc.

There's nothing magical about the shapes. They're just the family of shapes I chose to work with.

 

Broadicus,

You will need a bit of a thick skin around here.
We all have our biases, and some of us have trouble communicating, even with the best of intentions.

"Flack" generally shows something to be understood better. Actually a useful marker.

You can rate the interest in your thread by the number of pages of posts, in one way. So far you are doing well and have captured good attention.
Just go forward positively.

How many places could you go and have 30 people all saying the same thing? Not anywhere I have been.

Keep it up.

 

???

You deliberately and completely distorted my post yet you feel insulted?

Since I do not spend time arguing or insulting people whom I do not know on internet forums, please add me to your IGNORE list by using the feature provided by the forum here.

 

Thick skin you guys.
He's new but you are not, Tomas

 

He did the same thing in Doug's thread.
I'm not here for drama.

 

Bora, check out the curvaceous designs of Richard Newick's trimarans, especially from Three Cheers onwards - I think you will find them interesting.

 

Tomas,

I stand corrected.
Must have been feeling unusually generous, it will pass

 

Thanks, Gary - I'll take a look.

Tomas - forgive me if I responded a bit harshly earlier, but I have been sick since Sunday, and was probably just too sensitive about comments and things. But, if you are truly "not here for drama" as you said above, please drop it instead of continuing on about it in Doug's thread and in mine. Thanks!

UpChurchMr - Welcome to the thread! The topic is about the design and construction of trimarans with longer amas than hull bodies, if you would like to say something about that.

Tom Speer, thank you for your post about the hull shapes! That helped me a lot with understanding more the shape of the hull and its function. I guess the main thing is using what space you have efficiently to fit the given SOR. As far as my trying to understand how to use curves, I am making a little progress: I am having another look at Splines. My maths are not that great, so it could be some time before I make heads or tails of it all. Thanks again!

Thanks everyone for your encouragement, and my apologies for being "thin skinned" this week when I was sick. Please forgive me & blessings to you all!