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Fiberglass vs Aluminum?

Discussion in 'Technical Discussion' started by Blusky, Mar 2, 2014.

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  1. Blusky

    Blusky New Member

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    Hello, I am considering to design a watercraft (3m hull), and I have doubts about the material: fiberglass or aluminium.

    What do you recommend me? What are the main advantages and disadvantages of each material?

    Thank you in advance.
  2. K1W1

    K1W1 Senior Member

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    Hi,

    Are you going to design it or design and build it?
  3. AlfredZ

    AlfredZ Senior Member

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    Hi there,

    First, some good reading:
    http://www.yachtforums.com/forums/technical-discussion/6005-steel-aluminum-fiberglass.html
    http://www.yachtforums.com/forums/frequently-asked-yacht-questions/14469-fiberglass-vs-steel-hull-they-both-claim-best.html
    http://www.yachtforums.com/forums/general-yachting-discussion/17708-building-boat-need-advice.html
    http://www.yachtforums.com/forums/technical-discussion/14964-carbon-kevlar-fiber-hull-vs-steel.html
    http://www.yachtforums.com/forums/chris-craft-roamer-discussion/13971-steel-hulls-really-bad.html

    Second, you will find more results through the search feature.

    For have a lucrative discussion, try to give some more information, like the question in the previous reply, then what is the application? production or one-of? looking for speed, durability, rigidity, weight? Any thing you have in mind. Share your dream and vision in simple text form and you will get a discussion ready to go to the drawing board.

    Cheers,
  4. NYCAP123

    NYCAP123 Senior Member

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    Aluminum should be lighter and stronger, but more expensive and harder to work with. There is also the issue of bonding dissimilar metals that you won't have with fiberglass. Then there's the looks. In small boats you'll seldom see aluminum except in things like john boats where weight is a concern, so smooth lines are sacrificed. In much larger applications you'll seldom see fiberglass because strength is needed (although advances is fiberglass, or more precisely composites and coring methods, have made much larger applications possible).
  5. Capt J

    Capt J Senior Member

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    Guys, he's talking about a 10' boat. Aluminum would be easy to shape and weld. Otherwise I'd do a cold molded hull....also relatively easy to work with and can be light, but in that small of size Aluminum would be the lightest and strongest......
  6. Blusky

    Blusky New Member

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    Thanks for your comments and links.

    Probably Aluminium is more suitable, but FiberGlass is more easy to handle it and cheapest.
  7. Chapstick

    Chapstick Member

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    I'm curious about this NYCAP - pound for pound composites give much greater strength than aluminium, so what is the reason that an aluminium boat will be lighter and stronger?
  8. NYCAP123

    NYCAP123 Senior Member

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    First let me say that was a general statement. I'm not qualified to discuss the attributes of every type of composite material. It was based on what I've observed about building practices. Above a certain size the medium used turns to aluminum or steel. Also a lot depends on whether you're building a one-off or several boats, need for fireproofing and how rough the boat will be treated.
  9. Capt J

    Capt J Senior Member

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    Generally because it is easy to do a one off in Aluminum or Steel over 150' and the design can be changed from boat to boat. Plus you then have to store and move around this massive sized mold when you're not using it to build a boat. It probably takes the sale of 2 boats to pay for the cost of the mold and tooling to make a fiberglass boat. Fire proofing is much better with Steel over Aluminum and Fiberglass.