steel vs wood centerboard

Discussion in 'Boatbuilding' started by Jeff Daniels, Nov 25, 2011.

  1. Jeff Daniels
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    Jeff Daniels New Member

    Hi..
    Am restoring 11-foot flat-bottom lapstrake rowing/sailing skiff. Have been offered steel centerboard which I can cut to fit and build case. What are the advantages/disadvantages of steel vs wood and can build case to suit? Is steel advisable on this design?

    thanks

    jeff daniels
     
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  2. eyschulman
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    eyschulman Senior Member

    Steel is heavy may be good but it will corrode must use protective coating and keep after it(rubs off in box) and pin hole must be protected maybe plastic sleave. Wood has some similar problems while a glass foam board with some internal weight might be best if well done. Also very good but very costly would be nibral or other noble niclkel copper alloy.
     
  3. gonzo
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    gonzo Senior Member

    The steel board will make the boat more stable.
     
  4. BATAAN
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    BATAAN Senior Member

    How thick is this free steel? For an 11' skiff 1/4" is maybe too heavy and 3/16" plenty. You should closely check out "Pete Culler's Boats", a cheap paperback from Amazon full of good knowledge about flat bottom center board lapstrake skiffs, their problems and how to design around them, maintenance, sailing etc.
     
  5. PAR
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    PAR Yacht Designer/Builder

    An 11' lapstrake sounds like it's quite light. It would be very unlikely to employ a boiler plate centerboard in a design like this, as a hiking crew is more effective and not nearly as hard on the boat.

    A plate centerboard will need a beefy case, probably much more then what's there now. Save the steel for a bigger ballasted project and build a wooden or inert cored appendage, rather then burden an 11' boat with a hunk of steel that'll just rip out the case in short order.

    What design is it, as we'll probably have someone here that's familiar with it and it's appropriate centerboard. The simple answer is no a steel centerboard isn't recommended, but it could be a rare model with one. If it didn't have one, you'll test the rigging connections and the sturdiness of the case very quickly, if it's installed. In short, case design isn't an easy thing if you want it to stay together without leaking or causing other issues, like working the garboards loose.
     
  6. Jeff Daniels
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    Jeff Daniels New Member

    Thanks for the counsel. I am building case, and plan was for 2x3 white oak bedlog, 3/4 Marine plywood sides, bolted through 3/4 marine plywood bottom. Size calls for board about 10"X36". The boat is quite old, appears to be standard lapstrake double-row/sail design. I am reading various books, and the caution is apparent. I have some inadequate pix if interested in seeing.

    Again, thanks

    Jeff Daniels
     
  7. michael pierzga
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    michael pierzga Senior Member

    Remember that a steel plate centerboard presents a maintenance problem. Particularly the inboard section and bearing. If you must go metal , alloy would be much less maintenance. Wood will be the best.
     
  8. troy2000
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    troy2000 Senior Member

    Of course we want pictures. We always want pictures.:)

    And if it's anything besides a one-off home-built, there's a good chance someone here can identify it for you.

    How about a little back story, while you're at it? I'd be interested in hearing how you wound up with the boat...
     
  9. Jeff Daniels
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    Jeff Daniels New Member

    flat bottom wooden skiff, 11-ft.

    Hi...

    Thanks for the interest. Here is a not so great photo of the skiff. I have a second w/ interior where case would go, but cannot seem to find and attached through this forum media.

    Jeff Daniels
     

    Attached Files:

  10. PAR
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    PAR Yacht Designer/Builder

    I have no idea what that is, but I don't think you understand the forces involved in a centerboard case. I also don't see the need for a hunk of iron inside it. Most small craft (97% or so) do not have steel plate boards and don't need them. Just because you can get one, don't mean the design is well suited to it.
     
  11. BATAAN
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    BATAAN Senior Member

    I agree with PAR here. A wood board of 1" cypress or oak, edge fastened with 60d galvanized spikes with the heads cut off, driven in tight holes, and maybe a small piece (10lb) of lead cast into a hole in the lower corner of the board, is the traditional way to do it, not steel.
    This has made hundreds of thousands of work boats sail, and it will for you.
     
  12. PAR
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    PAR Yacht Designer/Builder

    I'd agree in that a strip planked board is the best way to go if using wooden methods. I've built dozens of these over the years, some with a small ballasting weight to insure they don't float, a few with lowering tackle. I'm now an inert materials guy on appendages. Using 'glass, composite or high density plastics is just the best way to go. The board or blade will never swell up, never rot, typically will last for generations with minimal care, etc.

    On a small boat like yours, many are tempted to use plywood or a wide piece of solid wood. Both approaches are poor for several reasons.

    Use this link to get an idea of how a stripped plank board is built.

    http://mothboat.tripod.com/CMBA/Building/foils.htm
     

  13. Jeff Daniels
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    Jeff Daniels New Member

    Par...
    thanks so much. I have been hesitating for just the reason you cite...just cause I can get it (steel) does not mean its right. Also, since the board and case are not yet constructed worrying through the right materials NOW is the time to do it. Thanks for the referral to the website, and for the other who have ideas on how to make it weight neutral.

    I think I now have a plan.

    Jeff D.
     
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