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blaze720 View Drop Down
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Post Options Post Options   Quote blaze720 Quote  Post ReplyReply Direct Link To This Post Topic: Designers
    Posted: 13 Oct 11 at 11:25am
Nothing wrong with self-draining double bottomed boats - it is much more about the amount and distribution of buoyancy, particularly in the cockpit area.    The wider the boat the more critical this distribution becomes as well.   It is just as easy to make a case for boats that don't self-drain adaquately being more prone to capsizing in the first place as their 'cargo' of water hardly helps !  Yes I know bailers can help, but not always.  .... and if they are righted and remain half-full they are very much easier to capsize again ... and again.

 I cannot be the only one who has seen the rig ripped right off righted Enterprises etc as they streugle to get the transom flaps doing a decent  job while lugging a ton or so of water around.  Particularly so in gusty conditions. 

Mike L.
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Post Options Post Options   Quote tickel Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 11:44am
Our Taser did not have a double bottom but almost always inverted. It was a real pain. Someone on this forum told me that it was designed that way so that it would not blow away....well it did anyway unless the expensive mast was stuck in the glue at the bottom of the lake. I am surprised that no one has mentioned the illustrious Lark. It rolled over easily, came up swamped and took ages to drain particularly as there was never just one capsize. British industry would not be in the decrepit state that it is to day were it not for Larks drowning all those promising Captains of industry while they were still students.
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Post Options Post Options   Quote olly_love Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 11:50am
Originally posted by oldarn

Originally posted by olly_love

But boats with little air pocked are more likely to throw you clear in a capsize,
also if you have ever been stuck below a boat with an air pocket then its not a nice experience, especially in waves. where you can get hit on the head alot. and can become very easilly tangled

I don't think L2Ks or Wayfarers go fast enough to throw you clear! If having been thrown clear, surely the boat is even more likely to turn turtle and then blow downwind.


sorry i ment boats with no airpocket you will be thrown clear,

there isnt much of an issue with an inverted boat blowing away from you, even the B14 on its side doesnt blow fast, as the rig creates so much drag and the underwater wing stops is moving, like a sea anchor,
the sam goes for anyboat when capsized, the main issue with blowing away is if they roll back on you,
TWO FRANK-Hunter Impala


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JimC View Drop Down
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Post Options Post Options   Quote JimC Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 12:02pm
I know from personal experience that both ICs and old school Cherubs with side tanks blow downwind faster than I can swim when capsized and on their sides.

Twenty years ago I had a Cherub with a sealed topmast on its wing mast, and that shot off downwind aat a very impressive speed: there was so much buoyancy that jib and kite halyard sheaves were clear of the water. Losing contact with that boat in the middle of the Solent was a very nasty experience - she even managed to be blown upright by the wind and head off downwind even faster...

Many thanks to these folks... Drop a couple of quid in the tin every time you pass them...
http://gafirs.org.uk/homepage.html

Edited by JimC - 13 Oct 11 at 12:03pm
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oldarn View Drop Down
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Post Options Post Options   Quote oldarn Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 12:31pm
Originally posted by blaze720

Nothing wrong with self-draining double bottomed boats -   It is just as easy to make a case for boats that don't self-drain adaquately being more prone to capsizing in the first place as their 'cargo' of water hardly helps !  Yes I know bailers can help, but not always.  .... and if they are righted and remain half-full they are very much easier to capsize again ... and again.

 I cannot be the only one who has seen the rig ripped right off righted Enterprises etc as they streugle to get the transom flaps doing a decent  job while lugging a ton or so of water around.  Particularly so in gusty conditions. 

Mike L.

May be Mike, the Blaze, and as Olly says the B14, that are the only two double bottomed self draining boats that don't turn turtle!

Mike, perhaps you are the only person who has seen the rig ripped off an enterprise. Sounds like rotten wood to me.
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Post Options Post Options   Quote alstorer Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 12:46pm
B14s can turtle, but generally only if you hang on the wing as they go over...
-_
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Post Options Post Options   Quote olly_love Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 12:49pm
Originally posted by oldarn

Originally posted by blaze720

Nothing wrong with self-draining double bottomed boats -   It is just as easy to make a case for boats that don't self-drain adaquately being more prone to capsizing in the first place as their 'cargo' of water hardly helps !  Yes I know bailers can help, but not always.  .... and if they are righted and remain half-full they are very much easier to capsize again ... and again.

 I cannot be the only one who has seen the rig ripped right off righted Enterprises etc as they streugle to get the transom flaps doing a decent  job while lugging a ton or so of water around.  Particularly so in gusty conditions. 

Mike L.

May be Mike, the Blaze, and as Olly says the B14, that are the only two double bottomed self draining boats that don't turn turtle!

Mike, perhaps you are the only person who has seen the rig ripped off an enterprise. Sounds like rotten wood to me.


i never said it wouldnt go turtle, just said it wouldnt drift down wind,
TWO FRANK-Hunter Impala


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Medway Maniac View Drop Down
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Post Options Post Options   Quote Medway Maniac Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 1:10pm
No, it isn't the double bottom that's the problem, it's the excessive side-tank buoyancy that makes many boats float too high, as Jim suggests. When the L2k and latest Wayfarers capsize, the double bottom doesn't even get wet - the side tanks hold it clear of the water!

Note that i'm talking about the latest Wayfarers. The old MkII's and Plus 'S' had no side tanks and floated nice and low on their sides; you could easily slither, seal-like onto the board and even a skinny individual like me could right the boat. Of course, they were full of water when they came up, but needed only the addition of a double bottom (and corresponding reduction of bow and stern tank volumes) to make that a non-problem. Owing to the volume distribution in such a double bottom, the boat would still sink pretty low on its side before the buoyancy of the double bottom stopped it sinking further, so there would be no great tendency to turtle and the centreboard would remain well within reach.

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Post Options Post Options   Quote oldarn Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 1:46pm
Is a good dinghy  design a boat that can be sailed in wind up to f7 and in fairly rough seas. That is the condition the early I14s might sail in, without decks and no self bailers.  Doesn't self draining and double bottomed cover for bad design and or bad sailing!
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Post Options Post Options   Quote Rupert Quote  Post ReplyReply Direct Link To This Post Posted: 13 Oct 11 at 1:51pm
Originally posted by oldarn

Is a good dinghy  design a boat that can be sailed in wind up to f7 and in fairly rough seas. 


Only if that was the design brief - a boat designed to sail in light winds and flat water might be an excellent design, but not cope at all in the conditions you describe.
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