Small Boat Build

Discussion in 'Wooden Boat Building and Restoration' started by ozzycouch, Jun 12, 2020.

  1. Blueknarr
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    Blueknarr Senior Member


    Our friend IKE could quote chapter and verse. There can be hollow spaces but they are disallowed for the emergency or secondary bouyancy caculations.
     
  2. hoytedow
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    hoytedow Carbon Based Life Form

    Screenshot_20200615-063649~2.png The boat looks ridiculously overloaded but wasn't. It was carrying lightweight but bulky items to an island campground on Hog Key near the Everglades for 3 nights of camping. The black chest was full of firewood. The bucket was empty. The trip back had more legroom. Very stable.
     
    Last edited: Jun 15, 2020
  3. hoytedow
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    hoytedow Carbon Based Life Form

    The squat boxes hold fenders, lines and extra pfds.
     
  4. hoytedow
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    hoytedow Carbon Based Life Form

    Since those deck plates o rings failed I replaced them with hatch covers. Message_1585422381220~3.jpg
     
  5. hoytedow
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    hoytedow Carbon Based Life Form

    Take it down? Boat has enogh foam flotation to support over 620 lbs., so, no.
    And that does not include the squat boxes themselves, which displace about 3 cubic feet or 180 lbs.
     
    Last edited: Jun 19, 2020
  6. ozzycouch
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    Location: QLD Australia

    ozzycouch Junior Member

    I like the way you think, I’ve almost loaded up the dingy for a camping trips, but haven’t had luck (Work/ bush fires/ covid) to get a trip in yet.

    Looking at the flotation, our local rules consider sealed compartments as air tanks (rightly so), and amongst other things have to be labeled with a caution. So no one sticks a fixing into the side...
    To avoid the labeling on such a small boat, I will just fill them with polystyrene.
     
  7. Will Gilmore
    Joined: Aug 2017
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    Location: Littleton, nh

    Will Gilmore Senior Member

    I take it, this means, only when using the space in question to calculate the floatation of a [edit: swamped, not "armored" (phone swipe:mad:)] vessel (emergency). Certainly there are lots of small craft with no flotation, think aluminum canoe, that still largely operate. Why would adding an enclosed airspace, make such a vessel less seaworthy. It sounds like the problem only lies in making certain claims about positive buoyancy.

    -Will (Dragonfly)
     
    Last edited: Jun 20, 2020
  8. hoytedow
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    hoytedow Carbon Based Life Form

    Commercially produced canoes have flotation in the ends.
     
  9. ozzycouch
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    ozzycouch Junior Member

    Hi Will, blueknarr is quoting the US standards, and I’m looking at Australian standards, so they are a little different.
    For the record, buoyancy seems to be calculated in this Aus standard with the two largest ‘air tanks’ disabled.
    And any boat with an engine requires positive buoyancy here.
     
  10. Blueknarr
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    Blueknarr Senior Member


    Enclosed airspace don't necessarily make less seaworthy. But are false security.

    Over a third of the hull breaches I repair are directly into buoyancy chambers. Without their stuffing those chambers would have no buoyancy at all and the boat likely would have sunk.
     
  11. Will Gilmore
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    Will Gilmore Senior Member

    [​IMG]
    [​IMG]
    [​IMG]
    [​IMG]
    No mention in the specs for the aluminum car top boat, of floatation.

    So... Are you all saying one is not allowed to build dead air spaces in, or just that you can't officially claim that space as floatation?

    They don't act as collision bulkheads?

    -Will (Dragonfly)
     
  12. ozzycouch
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    Location: QLD Australia

    ozzycouch Junior Member

    Hi Will,
    You can add in what ever you like. As far as regulations, just look up your local rules.

    I’m only against air space in my case, as they would have needed labels all over my boat. (Not the look I’m going for...)
     
  13. ozzycouch
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    Location: QLD Australia

    ozzycouch Junior Member

    So happy to get the boat up off the floor and on the trailer yesterday.
    C4AB37D8-27F0-41D9-B208-3F6E3C9BFDF1.jpeg
     
    Will Gilmore and hoytedow like this.
  14. SamSam
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    SamSam Senior Member

    I think you can probably forget going in reverse with sugar scoops like that. The flex and twisting/torsion could become an issue even when just going forward, as could waves coming in from the stern. Watch the seams to look for the possibility of the sides and bottom being pulled away from the transom. Pressure from the "trim tab" parts by water will want to twist and pry/lever the sides out on the transom.

    Flotation is mainly concerned with keeping a swamped boat upright and somewhat level so you can be inside while "sunk" awaiting rescue. The wooden boat itself will be neutral or even buoyant when submerged, so you want to put flotation in to counter accessory weight like motor, batteries, fuel tanks etc. If you put it in the bottom, there's a good chance a swamped boat would float upside down which isn't good as it leaves you outside the boat with nothing to hold on to, just the slippery bottom. If you put it all in the bow, the swamped boat might float vertically with just the bow sticking out of the water which isn't good. The best places are high up, like along the gunnels, or at least high enough to keep the boat from turning turtle when swamped.
     
    Last edited: Jul 19, 2020
    hoytedow likes this.

  15. ozzycouch
    Joined: May 2020
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    Location: QLD Australia

    ozzycouch Junior Member

    Hi Samsam, thanks for your thoughts on the transom and flotation. A quick look through the build photos will show the final set up for the transom that’s not going to fall to bits like it would now. And if I ever get a motor with reverse or neutral for that matter, I can test how bad it is!
    The flotation will be interesting, as you say up high is best. Have got a few areas that are high, the rest however are below seat level. I’ve tried to offset this a little by removing some buoyancy from the center/lowest part of the boat. Won’t know how it floats till I try and sink it. (Will need to do this anyway to get a builders plate)

    https://photos.app.goo.gl/1B2Qjv1X3GWzCvUbA
     
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