Steel yacht construction

Discussion in 'Boat Design' started by SeaSpark, Jan 6, 2008.

  1. Brent Swain
    Joined: Mar 2002
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    Location: British Columbia

    Brent Swain Member

    Steel

    It would cost a fortune to build a fibreglass boat that thick and it would be nowhere near as tough. Steel stretches to 1.4 times its original length before breaking ,and you can bend and fold it without breaking it. Not so fibreglass. A fibreglas hull of the same weight material as the one in the picture would have sunk ,period.
    Bang on a piece of fibreglas with a steel pickaxe, then try banging on a piece of steel with a fibreglass pickaxe.
    Origami hulls have conic ends , the only chine being amidships and below the waterline. Thus they are indistinguishable from radiused chine boats ,except for being better looking in the ends. They have proven that much of the framing in traditional steel boatbuiulding is totally redundant.
    An inch of foam will float 1/8th inch steel. Just do sufficent overkill for non floating items like ballast, machinery, etc . Wood has buoyancy equal to its weight out of water. However,the extremely remote liklihood of punching a hole you can't deal with in a steel boat may make these figures redundant.
    Brent
     
    1 person likes this.
  2. Wynand N
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    Location: South Africa

    Wynand N Retired Steelboatbuilder

    I had built a Dix 65 and the hull plating was only 4mm thick overall with 3mm deck. Of course it was framed and built in excess of ABS standards, but with clever design it is a "light" boat for its size. Displacement = 79436lbs (half load) compared to a fiberglass Irwin 65 with 78500 lbs displacement.
     
  3. jeff spinney
    Joined: Jan 2008
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    Location: nova scotia

    jeff spinney Junior Member

    not allot to mention here,everyone thinks their own material is best.clearly they don't see things like me,steal is best.I'm just kidding,i think the original argument was to do with the strength of steal in ANY situation from hitting bottom,to getting plowed by a steamer or even more likely, having to take on murslass pirates who will stop at nothing!!! Window glass is just as important though seeing how most of us have our non insurable electronics holding our windows up.Forget about just using you head,is their glass that will hold up in cold water,when you wish you were anywhere else? come back..
     
  4. Brent Swain
    Joined: Mar 2002
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    Location: British Columbia

    Brent Swain Member

    Steel

    Keep your windows too small to crawl thru and you won't have that problem.
    Brent
     
  5. jeff spinney
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    Location: nova scotia

    jeff spinney Junior Member

    yea i guess that's good advise,my windows are probably too big on my boat i have now but more windows cost more, and money helped make up my mind on a few things when i built it.
     
  6. timgoz
    Joined: Jul 2006
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    Location: SW PA USA

    timgoz Senior Member

    Jeff,

    What kind of a boat did you build & where are you up there? I've traveled through NS on several occassions on my way to NFLD & Labrador.

    Tim
     
  7. jeff spinney
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    Location: nova scotia

    jeff spinney Junior Member

    it's a cape island style lobster boat,fiberglass
     

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  8. Brent Swain
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    Location: British Columbia

    Brent Swain Member

    Steel boats

    I've built mostly my own designs from 26 ft to 36 ft, about three dozen of them so far. I'm on the BC coast, roughly 4,000 miles west of Halifax. I have a 31 foot twin keeler.
    Brent
     
  9. jeff spinney
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    Location: nova scotia

    jeff spinney Junior Member

    you'l have to post a few pictures,i love lookin at boats,guess it must get in your blood living next to the water,myself i have been fishing and building boats at my fathers boat shop(is where i built mine)for about 15 years now. Some years were more fishing than boatbuilding,but as of last year my brother and i took over at the shop.I still plan to fish, but mainly just lobster that is a 6 month on, 6 month off season.That gives me half a year for the shop,maybe later on will be diffrant but now we are pretty small time dealing with old boat repair.Anyway i 'd love to see anyones pics of boats,never know when you might see somthing you can use.
     
  10. la cage
    Joined: Feb 2007
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    Location: warragul,australia

    la cage Junior Member

    I will stick to my steel sandwich method,with fibgreglass on the outside " no electrolisis " timber/ carpert" interior, warm and cosy, zero condensation, interior encapsulated in closed cell foam ,positive flotation. Build in half the time for half the cost. ( not locked into an exspensive marine system.)
    Cheers from down under, Peter www.bourneboats.com.au
     
  11. rwatson
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    Location: Tasmania,Australia

    rwatson Senior Member

    Half the cost of what?

    You have a fibreglass hull, and steel re-inforcing - why not just use fibreglass and a foam sandwich and save on weight?

    You never did say if you could get insurance for your boat hulls either.
     
  12. Guillermo
    Joined: Mar 2005
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    Location: Pontevedra, Spain

    Guillermo Ingeniero Naval

    The image of the bumped sailboat initially posted by SeaSpark was also published at Yachting World magazine this last issue. Amazing!

    At the marina where I keep my boat in summertime, a couple of weeks ago a single moored GRP 10 m motorsailer was washed ashore by a gale, and it was smashed into pieces by the waves -literally- on the sandy and relatively protected beach! Incredible!

    Considering the resistance, small longitudinal flexibility for the hull, high ductility, absence of hydrolisis, easyness of repair almost everywhere in the world, etc, I vote for steel for long-term-go-anywhere cruising. Even if it corrodes, what can be avoided by a careful construction, good painting scheme and proper maintenance.

    And I agree with Winand: Over certain length there is not a reason for a well designed steel boat to be that heavy.

    By the way: fishermen around here (Galicia, NW Spain) don't like GRP boats except for the small planning or semi-planning ones. And in Portugal not even for those, as they prefer aluminium.

    Cheers.
     
  13. la cage
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    la cage Junior Member

    On launching my 12m, Yacht 7 years ago I had spent $50,000 AUS. At the same time a French production yacht was launched. $400,000. My Web site will explain the detail. " Insurance " I dont like boats that can sink." Hence the Bourne Method of Boat Building. www.bourneboats.com.au
    Cheers Peter
     
  14. Brent Swain
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    Brent Swain Member

    I launched my 10M sloop in 1984 . She cost me $6,000 to get her sailing and move aboard.
    Brent
     

  15. rwatson
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    Location: Tasmania,Australia

    rwatson Senior Member

    Both costings are pretty irrelevant.
    The itemised cost of materials and fit out details have to be done in todays prices to be any use to a new builder, and the labour estimates have to be based on 2 or 3 actual projects.
    Comparing a half million dollar boat with a $50,000 boat demonstrates a high degree of BS. Totally unconvincing!
     
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