fast, beachable 40ft monohull designs - suggestions?

Discussion in 'Sailboats' started by b.amateur, Nov 28, 2008.

  1. b.amateur
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    b.amateur Junior Member

    I like your hull, and also the construction method (as far as I understand it).
    It seems that you are not planning to use epoxy - for what reason?

    The K.I.S.S. principle was not meant to apply for the hull construction; rather for the rig and keel (no canting keels etc).

    Has this design been built already? And do you have a homepage or a link where some of your designs can be seen?
     
  2. Eric Sponberg
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    Eric Sponberg Senior Member

    The dirty little secrets....

    In Goulooze's write-ups, he refers to "The Dirty Little Secrets of Hull Design by Computer." Here is where the original is posted:

    http://www.newavesys.com/secrets.htm

    This article is written by my very good friend Stephen Hollister, the developer of the ProSurf hull design program, which is the one that I use for all my design. It is a very powerful and easy-to-use program, and this article is a very interesting read.

    Also, in Goulooze's description of his hull construction method, this is very similar to the stringer-frame method as described in the WEST System book, "The Gougeon Brothers on Boat Construction" (Chapter 22 in the 5th edition). I have used this method before, as in the design of my Delft 25 pocket cruiser.

    Finally, in Goulooze's description of the ultimate spar, his engineering reasoning is correct. Most stayed masts are "over-designed" in the middle and top by virtue of using a constant section extrusion which also has uniform wall thickness. This is a concession to low cost and ease of construction. Most stayed carbon fiber masts have a constant inner size and shape by virtue of the mandrels that are used for their construction, but they have an additional advantage over an aluminum spar in that their wall thickness reduces going up the mast because not as much strength or stiffness is required up high where the loads are lower. In a custom tapered mast, further reductions in section shape size and contribute to lower weight up high and to lower drag, all good benefits in a sailing boat. Engineering wise, these are very good reasons for using a custom tapered mast if the owner so desires. There may be some extra cost for such a rig because of the extra labor needed to build it.

    I do take issue, however, with the comment in the Ultimate Spar write-up:

    "If you don’t understand above importance you should not be at sea anyhow and certainly not if you have children with you. You better thank heaven that we are prepared to give you a fighting chance to survive in today’s changing climate (Read John’s Revelations)."

    I find this a little insulting and not necessary in marketing one's ideas. One does not have to completely understand all the technology of one's boat to enjoy sailing and a life on the sea. Also, I do not expect nor enjoy biblical references tossed at the reader in venues outside one's religous activities. But if you bleep over it, the engineering principles make sense.

    No disrespect to you, Goulooze, just an offer of constructive advice. Thank you for your contributions.

    Eric
     
  3. gouloozeyachts
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    gouloozeyachts Junior Member

    Thank you for the encouragement. To secure the wooden stringers in the slits of the FGRP frames a fillet of a stiff mixture of talcum powder/polyester resin should be used because the final lamination must stick to the fillets as well and this it will not do to cured epoxy. (Epoxy does bond to cured polyester GRP tough).
    The first strip starts about amidships and at  45 to the centerline and epoxy glued to the stringers (temporarily stapled) and the second strip so far apart that with a spacer a 25 mm line can be drawn on the near side of the second strip and trimmed to that line (more or less). The second strip will now be epoxy glued to the stringers as well. Between the stringers, small lengths of a cheap veneer + a piece of plastic bag will be attached to the inside of both strips with staples driven in from the outside. This are the temporarily supports for the FGRB ribbon which fill-in the 25 mm gap. The drawing we issued was created special for your application. We have an arsenal of designs of about 31 sizes in 4 ‘weight classes’ each with bow variants and keel designs and rig variations, making it about 900 variants. Where do we begin? Some 52 years ago, I popped into Mr. E v/d Stadt riverboat office, asking him for a design of a 9-mtr yacht. He showed me a new design (his own admission) and told me I would be the guinea pig. I would have been prepared if he had not given me one wrong answer namely that I could not change from strip planking to cold moulded ply. From there onwards, I went my own way. I understand your reservations. I can give a few references though few and far apart but very positive. We are in the process of opening a web site.
     
  4. Wynand N
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    Wynand N Retired Steelboatbuilder

    In the late 1980' or early 1990's I visited a boatyard in Mosselbay where a strip plywood boat was under construction and I was interested in buying one of those at the time. The shop was run by a guy called Maruis /or Martinus or some name similar if memory serves me right - his surname was Galooze. Not many Galooze's around, less so building boats..and was he was radical for the times when Roberts / Lavranos were king in SA and that spooked me from placing an order with him.

    I wonder if GaloozeYachts is the same person? I have changed views today and consider myself out of the mainstream and if this is the same person, pop me a PM and we can share some thoughts.
     
  5. masalai
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    masalai masalai

    b.amateur, From experience, do not let any of your family sail in or visit a cat, - - as we humans were made to walk on a horizontal surface, and pots, cups, plates and tables etc., demand to be horizontal to be effective... Think out of the box and go for a catamaran and have an appreciative wife....
     
  6. b.amateur
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    b.amateur Junior Member

    Thanks for clarification, Eric and gouloozeyachts!

    (Btw Eric, your Bagatelle looks great as well of course - and has the advantage of having been built already...)

    Although self-building is an option, I don't think with my lack of experience I would be the right guinea pig for a new design, however good it may be!


    I'll take care to keep my family away from the cats...maybe they'll enjoy it, but to me it just doesn't feel right, sorry. And they don't know what they're missing...
     
  7. gouloozeyachts
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    gouloozeyachts Junior Member

    Beste Wynand. I prefer to answer you in this medium. I do not remember you and your photo does not ‘ring a bell’. Yes, that was I and believe me I am getting more radical every day. (You have seen nothing yet) You mention some members of the old ‘gang’. At the time there was a clique called ‘the Cape mafia’ who blocked any newcomer in the yacht design/building or mast making etc. No editorials were given. Free adverts in annual publications always appeared with a missing digit in telephone numbers or any other means so that newcomers were not reachable. Editorials are essential in promoting ones business. Somebody else must say how good you are. You cannot do it yourself. The frustration of that, and coming out the amateur ranks, made me seek better, easier or cheaper methods to build and tried to ‘break-in’, but until now, no joy yet. Seen plugs from well-known plans of which moulds were to be drawn which did have so many bumps and hollows that the boats did not have to go to sea because the waves were already in the hull. I decided to do something about it and developed my hull design program. The first priority (special for the un-trained amateur) (no pun) is to have the frames perfect, obviating lofting. The outside being now quick and easy and with strategically placed ribs can the interior be just be bolted-on.
    Just found out that Mr. B. Amateur has decided to go for a ‘proven’ design. There are no facts that our designs are not ‘proven.’ Every yacht from our board comes from the same ‘program’ and is just a bigger/smaller version of some other real yacht. The basic data are just, established and constant. If the client is still not up to the job, we will be glad to wholly- or partly build for him.

    Mr. Sponberg. The majority of the public not grasping what I am trying to bring ‘home’ let me say things for may be one person in the thousands who follows my advice and improves his (and his crew) safety at sea, and that is good enough for me.

    I did look at you Delft 25. I do not think the application of the stringers is the same. Ours making it a grid (100 mm pitch)together with the closely spaced FGRP ribs (not sawn) acting as a semi honeycomb encapsulated with FGRP while your stringers stayed in because they are inside your sawn frames and have only a local mechanical advantage but not over the total area of the skin.

    Please tell us how to laminate 2 layers of 3/8 “ ply wood sheets without having some air pockets (unseen of course) without some real pressure arrangement. I think some of you construction methods are not fully controllable.
     
  8. Eric Sponberg
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    Eric Sponberg Senior Member

    Goulooze--Perhaps if you posted a picture of your construction method, that would help everyone understand what you are doing. In the Delft 25, I basically follow the Gougeon Brothers book on Boat Construction. When mating two pieces of plywood together, each side is coated with thickened resin (coloidal silica filler) so that the surfaces of each are 100% coated, and then they are stapled (later removed if metal, left in if plastic) together to assure contact. Yes, there may be the odd bubble here or there, but there would not be any large voids.

    Eric
     
  9. gouloozeyachts
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    gouloozeyachts Junior Member

    I am preparing a drawing encapsulating the whole process of skin construction and inside finishing-off. I guess you will understand even some rudimentary sketches but \the drawing must take part in my, to be developed, web site and neat and clear enough for any amateur to understand. (Just wishing that the person who’s rubric this is had chosen an other code name)
     

    Attached Files:

  10. Manie B
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    Manie B Senior Member

    Goulooze in my humble opinion i can see that you are a very clever man

    but you will never understand KISS

    i am a huge fan of the volvo race and that is high tech

    there are many many ways of doing it easier

    yours is smart - different - innovative - no doubt

    but not KISS

    jeez talk about the long way round :eek:
     
  11. Manie B
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    Manie B Senior Member

  12. gouloozeyachts
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    gouloozeyachts Junior Member

    Hello Manie

    Glad somebody agrees with my (late) mother on one point. I am adhering to K.I.S.S. al the time. Does it not mean KEEP IMPROVING (for) SAVING SOULS? My way of building strong, light affordable yachts and my tapered mast are only two examples I can show you. By the way, I like your modest use of the letter i. I wish I could be that modest.a
     
  13. gouloozeyachts
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    gouloozeyachts Junior Member

    At this very moment is there a yacht race from Cape Town to the island St Helena, a distance of some 1700 NM’s. (See http:// www. Governorscup.co.za) There were 15 entrants of which one is called ‘Moments”. This yacht, converted from an obsolete mould, was designed in 1984 as a cruiser and only finalized in 2005. ‘Moments’ is performing rather well for its size. The only remark one can make is that ‘Moments’ proves that our design float and sailing well. If a yacht must be proven first, what is the use of towing tanks? Those are for greatly reduced ‘mock-ups’ and if those are performing satisfactory the real yacht building commences. Due to a not optimal weight-distribution is ‘Moments not the front runner. The mould was heavily built and the keel could only be some 32% of the total displacement, limiting the heavy beating. Luckily the inclusion of our tapered mast takes care of some of the deficit of the ballast mass.

    Resume and closure:

    If we could design today’s potential winner some 25 years ago, think again, what we can do for you today!
     
  14. b.amateur
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    b.amateur Junior Member

    If somebody should stumble on this thread in his research for a similar boat as I am; I have found a design that comes very close to my ideas (even to some I had not dared to excpect; eg it is unsinkable):

    http://www.lnm-boats.com/index.php?option=com_content&task=view&id=45&Itemid=53

    http://www.lnm-boats.com/index.php?option=com_content&task=view&id=31&Itemid=45&Itemid=38

    it is also available as a kit.

    The boat described in the article appears to be for sale at the moment in Marseille.


    And the boat "Moments" described by Gouloozeyachts is this one (it came in third in the final result):

    http://www.capehorn.com/Moments1.jpg

    http://www.idw.co.za/Moments.htm

    A pity the skipper does not write more about his experiences (with sailing the boat I mean, not the building process...)
     

  15. Moments Skipper
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    Moments Skipper New Member

    What would you like to know about moments?
    She is quite a fast boat, but then I find that she is not as fast as a Muira, She Does not go upwind very well, nor downwind particularly fast. Reaching she is great.
    She was built by Mr G, as a boat I was told would be a race winner. Had I known that Mr G was going to build me a boat from an old mould, I would not have ordered her.
    Had I known that he would take so long to build it, again I would not have ordered her.
    The rudder that was supplied with the boat, de-laminated, and FELL off, 15 miles off Cape Augulus, and she had to be towed 100m to be repaired.
    The rudder that I had made by another boat builder performs better on Moments than the original one did.
    I think if Mr G was the type of person who would admit his mistakes, rectify the problems, and learn from the mistakes, by being honest and upfront with his clients, perhaps his boats would become marketable.
    As for his comment about having the wrong keel, an undersized one on Moments, this thread is the first time I have heard about it.
    The boat Moments is, is definitely not the boat that I ordered or was promised verbally by Mr G, and his Sales person at the time.
     
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