Carbon fiber in boat building?

Discussion in 'Boatbuilding' started by Andrus, Dec 4, 2010.

  1. Andrus
    Joined: Dec 2010
    Posts: 12
    Likes: 1, Points: 0, Legacy Rep: 14
    Location: 98

    Andrus Junior Member

    In automotive world, more and more parts are made of it and even whole cars from chassis.. etc.

    Are there any carbon fiber boats already out there?
     
  2. mark775

    mark775 Guest

    Yes. Goetz http://goetzboats.com/ does a good job, amongst others. When I worked for Delta Marine, http://www.deltamarine.com/, we used it to make large unsupported overhead panels and areas that were cantilevered. Cost/benefit analisis is the order.
    A noteworthy hull was by Nishii, Sterling. They forgot (or never knew?) that carbon conducts electricity.
    I don't know why it is not used more, actually, but for the expense. Seems to me that the job of many panels is to be stiff. Carbon does this well and a laminate could be commensurately lighter, with less resin. If the carbon expense would not be recouped immediately, I believe that lifetime fuel savings would surely make up for it. I plan on my next planing boat to be largely of it. Look a little deeper into how Goetz works, check out articles in Pro Boatbuilder, etc., and learn a really neat way to build. I am about to build an overhead for the cabin of my boat with it to maximise stiffness and headroom.
    I'd love to see what others are now doing with it. Thanks for bringing it up!
     
  3. Stumble
    Joined: Oct 2008
    Posts: 1,896
    Likes: 71, Points: 48, Legacy Rep: 739
    Location: New Orleans

    Stumble Senior Member

    Andrus,

    There are litterly hundreds of CF boats being built. In fact the boating industry has in large part driven the advancement of CF along with some aero-space dollars.
     
  4. Andrus
    Joined: Dec 2010
    Posts: 12
    Likes: 1, Points: 0, Legacy Rep: 14
    Location: 98

    Andrus Junior Member

    I have noticed lot of carbon fiber use when it comes to sailboats, but not much in motorboats. Clearly it is more expensive, but the cost is coming down so I expect we'll be seeing more use for it soon
     
  5. Stumble
    Joined: Oct 2008
    Posts: 1,896
    Likes: 71, Points: 48, Legacy Rep: 739
    Location: New Orleans

    Stumble Senior Member

    Andrus,

    the issue with power boats is that while CF is a great material it is still pretty expensive compared to fiberglass, and while it is lighter the weight savings are not particularly huge.

    So for a sailboat where the power is effectively fixed decreasing weight is a major gain in speed. But for power boats it is cheaper to increase power than to decrease weight. Of course there are boats at the far extreme like racing boats where price in no object and they are adding it, but for a pleasure boater the cheaper option is to go with bigger engines.

    For those power boats where top end speed isn't an issue, the justification for CF is even weaker, and again comparing the cost of CF to traditional materials shows it just isn't worth it.
     
  6. War Whoop
    Joined: Jun 2003
    Posts: 661
    Likes: 16, Points: 0, Legacy Rep: 84
    Location: Sunny Ft Lauderdale Fla

    War Whoop Senior Member

    S Glass would be a logical choice for a high end power boat,It can deal with the slamming loads better.
     
  7. susho
    Joined: Dec 2006
    Posts: 88
    Likes: 6, Points: 8, Legacy Rep: 78
    Location: the Netherlands

    susho Composite builder

    With the price of fuel going up, building in carbon fiber will get more interesting for motorboats too.
    but a cored glass/epoxy hull will be quite an improvement too, considering the more common polyester/glass layups.
     
  8. Herman
    Joined: Oct 2004
    Posts: 1,617
    Likes: 89, Points: 48, Legacy Rep: 1240
    Location: The Netherlands

    Herman Senior Member

    For high end boats, yes, carbon can be an option.

    For normal recreational boats: At least not the hull, as it will be noisy inside. Masts, spinnaker booms etc are always advanteous in carbon.
     
  9. Stumble
    Joined: Oct 2008
    Posts: 1,896
    Likes: 71, Points: 48, Legacy Rep: 739
    Location: New Orleans

    Stumble Senior Member

    While it is certainly possible to increase the use of CF in power boats I just don't see it as likely outside of the extremely high end price is no object designs.

    Just looking at the math for a moment, CF currently costs about $120/KG, and High quality glass work around $8/kg. Admitedly CF is about 1/2 the weight, so in relative terms the CF costs about $60/Kg over glass for the same pannel, or roughly 8 times the price of glass.

    Now since most high end boats are using laminate core construction, and the weight difference only applies to the shalls, not the core itself, the actual weight of a CF boat is only about 15-20% lighter than its Glass comparable. But at a cost of 8 times as much.

    Even assuming that you got a direct 15% fuel savings from the lighter weight, which is far from true... A 43' Donzi is running around $500,000 if the same boat were to be made in CF it would price out at around $1,000,000, though you would get 15% better fuel economy (under the terms of our hypothetical). Now to make back that roughly $500,000 by saving 15% of fuel burn, you would have to run something on the order of 5,000,000 gallons of fuel through the engines. (Yes that is millions of gallons)

    Now i don't know about you, but I can't imagine ever running enough fuel through these boats that the price of fuel would make sence. Note that this much fuel would equate to around 1.2 million refuels.
     
  10. mark775

    mark775 Guest

    How about a thickness critical application, a non-cored section (a hull bottom, for example, for us old guys that don't want a core) or a cored panel that doesn't need to be penetration tough, only stiff? Also, I believe you left off in your calculations that a panel could be made equivelently stiff and thinner with carbon, hense less weight and expense there. I don't know the expense of S-glass, tho I know what it is, and that might fit in there, too. Certainly a bagged or infused E-glass layup could save weight over not-careful hand layup and that's a start.
    Yes, the carbon's more expensive but less might be needed and less resin, too. I think a Pro-Boatbuilder recently answered this query in an article but their site is not-intuitive for me so I'm not searching.
     
  11. Stumble
    Joined: Oct 2008
    Posts: 1,896
    Likes: 71, Points: 48, Legacy Rep: 739
    Location: New Orleans

    Stumble Senior Member

    Mark,

    I can't find my issue, but I think it was the January 2010 issue. As I remember it the article basically found that for highly loaded members CF could be worth it, but not for the overall structure. I would point out that there are a lot of other advantages to a lighter weight structure, but in this application fuel economy just isn't a realistic one.
     
  12. CatBuilder

    CatBuilder Previous Member

    An update: Last I saw Eric, the entire new building was empty and there were little, if any employees. He's done, I think.

    He's now starting up a wind turbine blade company:

    http://compositeenergytechnologies.com/

    (he really needs to work on his marketing - wind guys don't care about boats)
     
  13. mark775

    mark775 Guest

    That's sad.
     
  14. michael pierzga
    Joined: Dec 2008
    Posts: 4,862
    Likes: 114, Points: 0, Legacy Rep: 1180
    Location: spain

    michael pierzga Senior Member

    This is sad indeed. A top class boat builder. I remember reading about his financial problems, but never fully understood whether it was the general economic situation or his bad economic choices when running the business. Boats are a terrible way to make a living.
     

  15. Andrus
    Joined: Dec 2010
    Posts: 12
    Likes: 1, Points: 0, Legacy Rep: 14
    Location: 98

    Andrus Junior Member

    looks like he also does car bodies(funny car body mold)
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.