50' performance cruising sailcat

Discussion in 'Projects & Proposals' started by vanquishcc, Aug 13, 2019.

  1. Alik
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    Alik Senior Member

    Home built boats in US for recreational use do not require certification, this is well known. From my previous post, where K.H. ferries are discussed, it is clear that I am talking on boats for commercial use. Boats for commercial use in US should comply to CFR, there are stability and equipment requirements.

    We don't have our designs in commercial service in US, thus I would rather rely on US-based naval architects to comment on these issues, for commercial boats.

    But we have our designs in commercial use in Australia ;) And for sure, those have to comply to NSCV, namely the structure to LR SSC rules if we are talking of 50+' multihull.

    The issue is: robe denney sets 40/20 persons on some of his boats, this would be treated as commercial/passengers boats. Not a 'home built - no certification' anymore.
     
    Last edited: Aug 24, 2019
  2. Eric ruttan
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    Eric ruttan Senior Member

    Was not the origional point that the K.H. boats are NOT certificated? Something you suggest is problematic?
    Are there? Have you shown that to be true?
    Are there no 50' multihulls in commercial use that are not compliant as you suggest?

    I think the point is you SAY that this is needed, but have not shown any evidence that what you say is true. And it is certianly not true in many cases.
     
  3. Alik
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    Alik Senior Member

    Eric ruttan, new member:
    Welcome new troll to the forum ;)
     
  4. Eric ruttan
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    Eric ruttan Senior Member

    So if you cannot answer simple questions about YOUR own points, ad hominem!

    Who's the troll?
     
  5. Alik
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    Alik Senior Member

    This is the way they market their designs. Lighter boats look more attractive, however the professioanl designer would include all optional equipment in light caft weight, as per standard. Amateur designers - we dont know what they include...
     
  6. rob denney
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    rob denney Senior Member

    Klaxon Diesels in Aus. Price was last year. There are also a couple of Chinese manufacturers whose prices are significantly lower, but you might want to order soon, before you are not allowed to.
    Rumars,
    Outremer 59: 15 tons empty, Catana 61: 19.2 tons light displacement, Schi0nning 60': 12 tonnes displacement. It comes as no surprise that the Schionning is not designed to your 'standards' and is lighter than the boats that are. Of course, all are far heavier (and much more expensive) than the Harryproa C60 at 4 tons. There are none launched yet, but the first one is well along the way, and on schedule for this weight http://harryproa.com/?p=488 The 50' strip planked harryproas all weighed around 2- 3 tonnes when launched, so we are pretty confident the infused foam/glass C60 will hit it's target.
    Eric,
    You seem to have hit a nerve!
    Alik,
    You are as wrong about insurance as you are about the usefulness of wave tank testing for catamaran capsizes, suitability of outboards, amateur builders, the engineering behind harryproas, the lack of relevance of the number of people on a boat to whether it is commercial or not and the plans and information needed to build a boat. As far as I know (and I am good terms with all my clients), none of the Harryproas (Europe, New Zealand, Australia, South America, USA) have had insurance problems or been denied access to marinas and the only one sold in Europe recently was sold 1 year after it was launched. The one that takes paying clients is the 15m/50' Blind Date, which takes sight and intellectually impaired people sailing in Holland. It, like the rest of the harryproas, is built and laid out sensibly and suitably, rather than to one of your generic rules which do not apply to such a boat. It is now 10 years old, still going strong.
     
  7. Alik
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    Alik Senior Member

    You only forgot to mention about service of cheap exotic engines. Engine without prompt service and spare parts is useless, but You will never tell it to your amateur boat builder.

    If You want to be part of professional marine design community, go and study, get proper engineering degree. After that, You might probably get understanding of what people with qualification say. Otherwise, everything You write here is ignorant amateurish crap and the designs You are offering for sale are potential hazard, they are substandard and have no record of any certification. The designs You offer for 20/40 persons are passenger craft, they won't be legally allowed to operate as such in most of countries, don't fool the boatbuilders.
     
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  8. Alik
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    Alik Senior Member

    Regarding catamaran capsizing and model testing, here is well known research paper by Wolfson Unit, UK:
    http://www.wumtia.soton.ac.uk/sites/default/files/1441_merged.pdf
    There has been ongoing research for many years now by the same group, we follow their publications.

    But of course, 'proa fetishists' without engineering degree know the phenomena better than leading research laboratory ;) Sounds ridiculous.
     
  9. Eric ruttan
    Joined: Jul 2018
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    Eric ruttan Senior Member

    Dude, you are toxic.
    You know nothing about said engines, nor about Robs experience and knowledge of them.
    Why assume your limited education entitles you to know and others cannot know?
    As an aside, diesels are not known for needing repair. And China the largest producer of them.
    As an ambassador of your profession, why the hell would anyone join it after seeing your behavior?
    Fortunately Rob has done buisness with many skilled engineers who are not... like you.
    Vague acusations and assertions you cannot back up? Goto school to learn that? WTF
    Says you. And it's Not backed up
    Assumes facts not in evidence.
     
    Last edited: Aug 25, 2019
  10. sailhawaii
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    sailhawaii Junior Member

    Back on topic....

    I've been working on my design (44' performance cat) off and on for about 2 years now and as an inexperienced designer I thought that would be the same thing I needed help with. I was also meet with a lot of discouragement from some people on the forum. I have spent 10 time the amount of time reading and studying boat design that I have actually working on my design.

    I have made it as far to design it all flat panel in Rhino, cnc cut a scale model and put RC gear in it and sail it around. I have already made changes based on what I learned and plan to make the next model. Then I plan to build a 11' to 16'scale model without the cabin that I can actually sail in.

    In the end I may actually just build a Schionning design (from plans not a kit). I haven't decided yet, but either way I have learned a ton and had a great experience. My estimate is a 10yr build not 5years. Even if I buy plans, I understand how to work with composites and build a strong structure from all my experimenting.

    IMHO too many professionals are too quick to discourage, and to many beginners (myself included) underestimate what the process takes. Everybody has different objectives of why they want to do things one way or another, for me I care less about resell. It's about the journey not the product. But, I only am willing to risk my life in something I have a lot of confidence in... and after two years I'm not there yet.
     
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  11. Rumars
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    Rumars Senior Member

    This is misleading because you and at least the european boats you cited do not use the same definitions for weight, nor are the boats similar in living space, fit and finish. The european boats use ISO 8666 for light displacement wich include everything on the boat except people, stores and liquids (fuel/water/waste). Max loaded displacement includes those also. Now you on the other side don't say what your numbers include, but on the C50 page we read: "*Note: additional payload (water/fuel tanks, small generator, batteries, stowage, personal gear, etc) over and above the 2 tonnes can be added to the lee hull at the expense of speed, but not seaworthiness." Your C60 does not say that but you want me to compare it to a Outremer 5X. C60 payload is 3000kg and I don't know your starting point. The Outremer5X has 5200kg of payload just for people, food, liquids and personal belongins. For the 8 people it is homologated in voyage mode I have 8x75kg (people) and the rest of 4600kg is free, for example 8x325kg food and personal belongigs and 2000kg for fuel, water and waste.
    Now we come to the real problem of comparing the boats: living space. The C60 is probably half the boat the cat is since you have one 12m hull and half a saloon plus two single cabins in the other hull. Fit and finish are a personal choice and I won't adress it, but it impacts light displacement.


    The european law is clear, homebuildt boats can not be sold in the EU for 5 years after the first registration. So if a boat was sold 1 year after launching there are 2 possibilities:
    1. The boats registration is older then it's launching. Common occurence with homebuildts.
    2. The boat was sold outside of the common market (meaning she will not be registered in the EU).

    I am really curious about "Compaen" (formerly "Blind Date") and maybe you can clarify:
    The boat was buildt in the EU by a professional boatbuilder and is certified for passengers (12 guests and 3 crew). This means there are following possibilities:
    1. The boat was buildt under an RCD extemption rule.
    2. The boat is RCD compliant, wich means someone did the relevant documentation and we have 2 options:
    a) your engineering was considered sufficient
    b) someone modified your boat structuraly
    The boat sails on what is now a big lake (IJsselmeer) so what design category was she put in? Is the boat allowed to go out into the open sea with passengers?

    I don't understand why you insist in comparing your proas with equal length catamarans. Your boats do not offer the same living space or payload. Yes they are lighter but that has nothing to do with rules and standards, it has to do with having the mast on the hull, not having half the living space and less payload. The speed potential is sadly unproven to this date for the Harryproas.

    If you compare the Schionning to the Outremer you have 12400kg vs 14800kg displacement but the payloads are 3500kg vs 5200kg. So asuming Schionning uses the same ISO8666 displacement definition and taking ito acount the payload difference the difference in weight could simply be fit and finsh.
     
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  12. Alik
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    Alik Senior Member

    We will never know the truth ;) Only shameless promotion of proa fetish.

    P.S. The next claim will be '50' proa has same accommodation as 50' cat' ;)
    In our practice, we use two objective factors, to compare designs and types of craft:
    • (accommodation area)/(total plan area of boat)
    • (accommodation area)/(number of persons on board)
    Say, we did this comparison for different types of small passenger craft in: Nazarov A., Jabtanom A., Charatsidis N. Small Passenger Boats and Water Taxis: Aesthetic and Functional Aspects of Design //Marine Design Conference, RINA, 2014 - Coventry, UK. p.83-94. Can use this approach to other types of craft.
     
    Last edited: Aug 26, 2019
  13. Eric ruttan
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    Eric ruttan Senior Member

    Can you clowns take this bashing to another thread unstead of crapping all over this one?

    oh come on! a ton and tonne is ~+- 10%, but really, 15 to 4 is sooo much different to 13.9 to 4. How many Hail Marys is that? REPENT ROB!
    And? Of course they are different... The point is one is 1/3 the weight/materials/cost to the first order than the other. Everybody but you got that.
    And? You can add the payload how you like. Home builders like to do things for themselves. Some add solar panels and others generators. Some want 100gal of water stored, others less. Its called freedom and choice. But if you are real interested in one of Robs super light fast and cheap boats (you can pick 3 out of the 3 here) I am sure you can email him and he will detail it out for you. He may even give you OPTIONS!
    more stupid bias.
    There is ONLY ONE WAY to compare boats. Its cost. Its the only thing that matters.
    See the assumption is that accomodation or length is a stand in for cost. But its not. I mean, it is if you are comparing this mono to that mono, or this cat to that cat. But when you start challenging assumptions, all that goes out the window.
    But it is hard to get people to see things like that. So I cannot fault you for being slow on this point.

    I don't know why you insist on insisting he insisted.
    Rob casually offered a comparison. He did not insist it was the only possible comparison. You did that. If you don't like it fine. You wanna compare it to his 80'? Go right ahead.
    Except those over 24m, right? You really like that 80' I guess.
    Says you! Per DOLLAR they sure as heck do. But hey, how about you go make a ISO standard about how to compare different boats?
    If you biases are just right, you can get to any conclusion you like. Why not
    (accommodation area)/(total displacement of boat)
    Or
    (accommodation area)/(cost of boat)
    ?
    See, it seems your assumption is all boats are very simular. And they are not.
     
    Last edited: Aug 26, 2019
  14. Deering
    Joined: Feb 2005
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    Deering Senior Member

    Thanks. I’ll look into them. My guess is that they aren’t sold in the States due to air emissions standards.
     

  15. Rumars
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    Rumars Senior Member

    I'll tell you why in simple words:
    A guy walks into a car dealership and asks for something big and powerfull and nice, say like an Escalade, but maybe not so expensive please. The salesman says no problem, but instead of offering a Suburban he says here, we have this Malibu, does everything the Escalade does, at a third of the price. And look if that's to expensive we have the Chevy Spark, great car, gets you home just like the Escalade.

    If Mr. Denney would represent his boats correctly all would be fine. He could just say hey, I have a cheaper boat for you but to get the same interior and payload as you desire you must go much longer than a cat. The boat has a great speed potential on paper, and is comfortable and safe in big seas, but I can not prove it to you. I can not even show you a boat of this model because all that are buildt are older models, not the new thing.
    But look, if you are willing to risk designing and homebuilding a big cat then you certainly can risk building my boat, if you are willing to take the tradeoffs.

    In the EU 24m is the lenght limit for a recreational boat. Everything over that is considered commercial craft regardless of actual use, and is subject to the rules governing construction and operation of it's flag state authority. Like it or not that is EU law.
     
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