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Weight equalisation

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Post Options Post Options   Quote 423zero Quote  Post ReplyReply Direct Link To This Post Topic: Weight equalisation
    Posted: 03 Jan 22 at 10:08am
The wire is purely to support your weight, positioned correctly it offers support for your back.
Robert
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Post Options Post Options   Quote tink Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 10:02am
Originally posted by iGRF

Originally posted by Oatsandbeans

Exactly right-the only thing that matters for the righting moment is the distance from the centre line to the centre of mass of the sailor. You don’t have to think about anything else it will just confuse your thinking (a bit like the lee bow effect conundrum!)
Ah but I’ve proved myself correct time and again with my tidal lee bow theory’s by winning race after race, just as my hook height theorys proved correct in windsurfing as I pioneered lower and lower hook height in the early days. However I’m not claiming to know this one, which is why I’m asking the question and so far nothing written here so far has convinced me not to try. I think like lots of things y’all have been doing it wrong all these years 😉

As I said yesterday windsurfers are different because the mast mast is able to tilt relative to the position of the centre of buoyancy. I would draw another picture but it won’t have any impact on your thinking and I’m going sailing instead. 
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Post Options Post Options   Quote iGRF Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 10:01am
Originally posted by 423zero

Think about the angle the wire is from your body to the mast, it's not much off vertical, if you stood at the side of your boat and tried to tip boat on its side using the exact same angle, you wouldn't tip it over.
Youve just made the case for me. Exactly why moving the wire further away helps pull the boat over.
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Post Options Post Options   Quote tink Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 9:57am
Originally posted by iGRF

Lot of cack handed thinking here. It’s the mast and sail attached to it that’s trying to tip the boat over. So just as fatter head sails have more adverse heeling moment so does having a wire attached to the mast high up to counter the heel What then happens the combine weight downforce is spread to weather . The bigger the wire angle the further to weather. Taller helms therefor being faster and able to sail the boat flat,
I agree with the issues having a too high hook would cause in lulls a consequence of my thinking marred by years of having a boom to hang on if necessary, but I think I might have a work around. The point still wrankles though as to why so many think it’s wrong

I believe professionally you where something in marketing I am an Engineer. The wire and where it is attached to the mast or the person has no effect of the righting moment. The only factors are total sail force, effective height of sail force, how far outboard the crew weight is and the crew weight 

Think about a TOY unstayed mast and sliding seat no wires, wind increases more force in sail sailor moves outboard more on the seat it’s that simple. 

The trapeze wire and the shrouds are irrelevant 
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Post Options Post Options   Quote iGRF Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 9:56am
Originally posted by Oatsandbeans

Exactly right-the only thing that matters for the righting moment is the distance from the centre line to the centre of mass of the sailor. You don’t have to think about anything else it will just confuse your thinking (a bit like the lee bow effect conundrum!)
Ah but I’ve proved myself correct time and again with my tidal lee bow theory’s by winning race after race, just as my hook height theorys proved correct in windsurfing as I pioneered lower and lower hook height in the early days. However I’m not claiming to know this one, which is why I’m asking the question and so far nothing written here so far has convinced me not to try. I think like lots of things y’all have been doing it wrong all these years 😉
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Post Options Post Options   Quote 423zero Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 9:50am
Think about the angle the wire is from your body to the mast, it's not much off vertical, if you stood at the side of your boat and tried to tip boat on its side using the exact same angle, you wouldn't tip it over.
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Post Options Post Options   Quote iGRF Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 9:38am
Lot of cack handed thinking here. It’s the mast and sail attached to it that’s trying to tip the boat over. So just as fatter head sails have more adverse heeling moment so does having a wire attached to the mast high up to counter the heel What then happens the combine weight downforce is spread to weather . The bigger the wire angle the further to weather. Taller helms therefor being faster and able to sail the boat flat,
I agree with the issues having a too high hook would cause in lulls a consequence of my thinking marred by years of having a boom to hang on if necessary, but I think I might have a work around. The point still wrankles though as to why so many think it’s wrong
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Post Options Post Options   Quote Oatsandbeans Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 8:49am
The shrouds don’t really come into this. The loads are balanced when the rig tension is applied and yes the windward one’s tension will change whilst sailing it doesn’t contribute to the heeling effects. The simplest way to get your head around this ( probably been said earlier) is to see the problem as two balanced moments (turning forces) one from the rig and the centreboard and the other from the crew weight and the hull buoyancy.
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Post Options Post Options   Quote tink Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 8:25am
How sail boats work (simplified)
Imagine all the sail forces act from a point F1 a distant D1 above the centre of buoyancy of the hull (red dot)
The sailors weight acts about F2 a distance D2 horizontal from the centre of buoyancy 

To stop swimming F1 x D1 must equal F2 x D2 

The wire is completely irrelevant 




Edited by tink - 03 Jan 22 at 8:26am
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Post Options Post Options   Quote Oatsandbeans Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jan 22 at 8:19am
If you sit on the side then put your weight on the wire, yes the tension in the shroud will reduce as the mast is now supported by two wires. Not quite sure how this helps.
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