Carbon fiber in boat building?

[Andrus]

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?

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!

[Stumble]

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.

[Andrus]

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

[Stumble]

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.

[War Whoop]

S Glass would be a logical choice for a high end power boat,It can deal with the slamming loads better.

[susho]

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.

[Herman]

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.

[Stumble]

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.

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.

[Stumble]

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.

[CatBuilder]

Originally Posted by mark775

Yes. Goetz http://goetzboats.com/ does a good job, amongst others.

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)

That's sad.

[michael pierzga]

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.

[Andrus]

looks like he also does car bodies(funny car body mold)