a canter,not

Discussion in 'Sailboats' started by Timothy, May 12, 2008.

  1. Timothy
    Joined: Oct 2004
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    Timothy Senior Member

    I just read the thread on Procyon and got to thinking about movable ballast and as I have recently been contemplating making a set of legs for my center board boat I came up with this. Legs transverse ballast and shallow draft all in one. The idea is based on a memory of the hand crank ringer mechanism of my mothers washing machine. You can probably deduce from this that I am not a young man and this proposal is evidence of the onset of dementia. Animation attached.
     

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  2. tspeer
    Joined: Feb 2002
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    tspeer Senior Member

    What's the point of having the ballast in the water? It would be a lot less drag to turn the whole mechanism upside down and put it on the deck. No potential for leaking into the boat, either.

    The boat would be much lighter if instead of moving weight to windward, you moved buoyancy to leeward. Or do some of both. For the same weight as one of your bulbs, you could have a larger, streamlined structure that would have substantial buoyancy. You could use a modest amount of heel of the boat to put it into the water when needed or lift it out of the water when not needed, instead of translating it back and forth. Then you could get rid of the motor and rack-and-pinon - a fixed arm to each pod would suffice, because when the leeward pod was in the water, the windward pod would be out of the water. So the leeward pod would act like negative ballast, reducing the displacement of the hull, while the windward pod would act as positive ballast. Since they arms would be fixed, the crew could move to the windward pod, making their weight far more effective. I believe a gentleman named Victor Tchetchet once proposed something like this.
     
  3. Timothy
    Joined: Oct 2004
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    Timothy Senior Member

    I am not seriously proposing that this would work. My thought was that a transverse movable ballast system kept under the boat and with in the beam of the boat ,while no where as efficient as a canting keel. might be handy for a shallow draft cruising boat, with the added benefit that the boat would stay level when high and dry at low tide. If the strut were curved forward then the bulbs could be made to align with the flow as presumably the boat would be making more leeway when close hauled and the bulbs are extended for the appropriate tack. Since the only extra hole in the boat would be for the shaft to the rollers, a simple stuffing box could be used to keep the water out.I thought that because of the greater lever arm less internal ballast could be used or more sail and a higher aspect rig could be utilized.I only came up with this idea because I just read that Procyon used gravity to move its keel from side to side when tacking which I thought would work just as well with two bulbs on a single transverse strut,and that one of the main problems they had cruising with the boat was excessive draft. I realize that multi hull is the way to go but why are canters the rage?
     
  4. Timothy
    Joined: Oct 2004
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    Timothy Senior Member

    I woke up this morning and after reflecting on Mr Spear's comments came up with this. Just above the waterline and enclosed entirely within the hull It loses the legs capability but is,I think , more efficient and gets rid of the drag problem at the expense of taking up some interior space. But on a center boarder this is a problem any way. I worry that the boat would be tender and stable inverted as the boulbs would now be above the waterline.
     

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  5. oldsailor7
    Joined: May 2008
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    oldsailor7 Senior Member

    Lol. tspeer. :cool: I love it.

    That was in 1945 and he coined the name "Trimaran".

    I had the privilege of meeting him on the dock of the Mirimar yacht club, NY.
    in June 1969.

    It was before the start of the multihull New York-Bermuda race. We were standing looking at Dave Greens brand new Crowther Kraken 40 trimaran.

    "What do you think of that Victor" I said. With tears in his eyes he said "I have lived to see this".

    He died later that year.
     
  6. Doug Lord

    Doug Lord Guest

    On-deck movable ballast

    This is a design concept by Julian Bethwaite and Martin Billoch;it was designed with on-deck movable ballast. It was conceived of as a monohull with buoyancy pods-and the pods weren't to be used in normal sailing-emergency backup only:
     

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  7. oldsailor7
    Joined: May 2008
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    oldsailor7 Senior Member

    GOOD GRIEF DOUG. :?:

    Thats neither fish nor fowl. :eek:
     
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  8. Chris Ostlind

    Chris Ostlind Previous Member

    As well as non-existent for many, many years now.
     
  9. Doug Lord

    Doug Lord Guest

    ===================
    Not true. As I mentioned earlier, it is a "design concept" and as such remains alive and well. As a matter of fact, the concept has been tested for years on rc models and is being incorporated on my new boat as well.
     

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  10. oldsailor7
    Joined: May 2008
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    oldsailor7 Senior Member

    I would hate to be going fast in a rough sea and have one of those arms dig into a wave. :eek: :eek: :eek:
     
  11. Doug Lord

    Doug Lord Guest

    It's not much of a problem.....
     

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  12. Chris Ostlind

    Chris Ostlind Previous Member

    So, now the Bethwaite/Biloch boat is a foiler, is it? Those pictures you posted show nothing of the kind, yet here you are making comparisons to a foiler when it's mentioned that there are problems with extended racks on monohulls.

    The term among friends, here, is IRRELEVANT.

    It's more than simple, Doug... Prove It. Prove that a sailing foiler can lift its crew, its own hull and the weight of a bulbed keel and that it is sailable AND (and this is probably the best point) that anyone in their right mind would want to bother.

    You know, these days there is a wonderful low cost method for proving that of which you speak. It's called Youtube.

    Avail yourself of the medium and show us how it can be done. Show us it is more than a hardware store collection of funky pieces going nowhere.

    Until then, it's a pipe dream and... like I said... non-existent.

    The ball is in your court, my friend.
     
  13. Chris Ostlind

    Chris Ostlind Previous Member

    Racks in the water?

    I think that was a good question.

    Photo courtesy of Sailing Anarchy and www.am2.org
     

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  14. Doug Lord

    Doug Lord Guest

    =========================
    It's not much of a problem...... If a boat is designed for them racks work very well whether it has on-deck movable ballast or not and whether it has foils or not. The use of racks to support on-deck "movable ballast" has a long and successful history. One of the Herreshoffs designed a monohull using inanimate on-deck ballast and he really liked it. Whether the ballast is inanimate or not it can be very effective at deck level and clear of the water. The point I'm making is that on-deck movable ballast has tremendous potential to help mono's or multies go fast:
     

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  15. Chris Ostlind

    Chris Ostlind Previous Member

    While I've truly enjoyed the littel sidebar exploration of your senses, here, Doug... what d'ya say you retool the conversation a bit and get it back to the original intent of the thread starter, Timothy.

    You know, just out of courtesy?

    I just love the plethora of imagery you can gin-up regarding foilers and all, but the T-Man didn't go there with his original presentation, nor did Speer with his comments. So, what d'ya say you give some respect to Timothy and his efforts to get some info without dropping yet more stuff about foilers and all that the name conjours for you?

    Yes, I'm respectfully restoring some order to the thread's originator. Can you do that? Timothy is looking at something distinctly different from your penchant for all things foiling. Jokes and sidebar commentary aside, I think he deserves the respect of putting your comments on point.

    Don't you?
     
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