Amateur wants to build Blue water multi hull cruiser

Discussion in 'Multihulls' started by nickvonw, Oct 13, 2009.

  1. nickvonw
    Joined: Oct 2009
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    nickvonw Junior Member

    nice cleats alan...

    pretty smart..especially if they were cheaper than stainless ones...maybe stronger too???

    what is the durability of duflex like????how many layers of epoxy and glass do u put below the water line???strength compared to alloy?? did u look into alloy coinstruction..it looks like the duflex kit method looks like the easiest fastest way to go for a home builder...


    did u look into plywood?? does anyone have any experience with plywood epoxy construction???

    nick
     
  2. Alan M.
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    Alan M. Senior Member

    Every material has it's pro's and cons. I'm not a welder, so I'd either have had to learn to weld on my own boat, which would be a worry, or pay a professional to do it. Which to me, isn't quite the same thing as building your own boat.

    Also I doubt an alloy cruising boat would turn out as light as a Duflex one, once you fit all the lining needed inside. You can just fair and paint the inside of Duflex.

    Then there's the difficulty of painting aluminium, and having to use antifouls with no copper.....that's not to say aluminium doesn't have some very good points - but it has it's downsides too.

    Once I had handled some Duflex, I just liked it. It's already glassed both sides, so it saves work compared to plywood, the panels are incredibly stiff, straight and light, they don't get mouldy or warp....

    It has it's downsides too - it's not cheap for one, and you have to be careful to de-core and fill or glass over every exposed edge - screwing on fittings becomes a much bigger job - where with alloy it would be a simple drill and tap job, or with ply, just screw straight on, with Duflex you have to drill a bigger hole, de-core and epoxy fill, then drill again.

    Plywood isn't anywhere near as much of an up-front financial commitment. Once you have the shed, you can buy some ply, glass and epoxy and get started without really spending serious cash. Probably similar with alloy.

    It's probably more a matter of what suits your current budget and location than one material being that much better than the other.
     
  3. Fanie
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    Fanie Fanie

    Learning to weld properly is certainly an asset. This is what the SS cleats look like I made myself - compared to the buying price they cost next to nothing, I also get a kick out of making it myself.

    People for the most part is eager to share what they know, just look at the forum. If you go to a pro welder and ask him what to look for and spend a little time on something then it's not that hard. We sometimes forget to compliment those that so freely share their expertees - so when someone does teach you something do spread the word. Next time they may help you again.

    I'm not saying your composite cleats are not good or not strong enough, but scarfing is going to show up and you are going to keep on painting them.

    So far I've made quite a few items, cleats, blocks, anchors and it will end with the trailer. Calculated it's quite a bunch I'll be saving by doing it myself.

    Now, ask me if it was worth it so far :D
     

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  4. gonzo
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    gonzo Senior Member

    You can buy SS cleats for about U$13.00 at Harbor Freight. Between the cost of materials, electricity and wear and tear on equipment I don't think you are saving any money. Also, the design on that cleat is poor. The horns should taper so the line tightens as it pulls. The taper makes it easier to loosen the line too.
     
  5. Fanie
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    Fanie Fanie

    Actually I have seen similar on the internet, no tapers. Maybe I made these wrong, the line loosens easy. The materials was relaive cheap, and what wear and tear on equipment ? The macine goes on to weld and off when done, which is what I got it for :D Also, besides being a ripoff price (you forget where I am) the ones for sale didn't impress me.
     
  6. sailsocal
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    sailsocal Junior Member

    De-coring and filling duflex holes prevents absorption of moisture, right? So wouldn't you want to do the same thing with holes in a plywood core?
     
  7. Scrumble
    Joined: Aug 2008
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    Scrumble Oram 46'C MS Builder

    I do when placing ply as a dense core replacement in duflex.

    http://scrumbleproject.wordpress.com/2009/06/02/bonding-the-aluminium-backing-plates-for

    Alan, Thank you, I have enjoyed the discussion and know that my boat will come in at less than 250K AUD, a bit more than you due to the diesels and V drives.
     
  8. nickvonw
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    nickvonw Junior Member

    would alloy be tougher in the long run....if u are running thing up onot beaches etc

    also would alloy be less maintenance with painting etc??? also would have to fair alloy at all??? why fair alloy?? is it purely asethetics???

    n
     
  9. jamez
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    jamez Senior Member

    The look doesn't suit everyone but you don't need to paint an alloy boat at all topsides. Something very appealing about a boat that never needs exterior repainting above the WL. I have no idea what it costs to paint a 45-50'BD cat, but I would imagine a significant cost and time saving over a number of years if it wasn't necessary.
     
  10. Alan M.
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    Alan M. Senior Member

    And your cleats! :eek: :D
     
  11. Alan M.
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    Alan M. Senior Member

    Fairing any material is pretty much all about asthetics.
     

  12. Alan M.
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    Alan M. Senior Member

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