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Steve411 View Drop Down
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Post Options Post Options   Quote Steve411 Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 12:00pm
Originally posted by Steve411

sbolland by you.

Another well-engineered unstayed rig. The main thing is that kicker tension is the key sail control as kicker tension, mast bend, sail fullness and leech tension are inextricably linked. You can't have a tight leech for pointing without flattening the sail off for example.

Downwing the unstayed rig makes life interesting as gusts bend the mast forward making nosedives more likely. Unlike stayed masts we use kicker tension to depower downwind (bend the mast and therefore flatten the sail) whereas it's more normal with a stayed rig to blow the kicker downwind (on boats with kites at least) to depower.

Pic by www.malcolmlewinphotography.co.uk

OK, here's the pic!

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alstorer View Drop Down
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Post Options Post Options   Quote alstorer Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 12:10pm
Ok, whilst we're on the subject- the floppy stayed rig of the Solo- what the hell is that all about?
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Post Options Post Options   Quote Adam MR 1137 Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 12:26pm

I have posted this in fav pics thread but a perfect example of an unstayed rig bending of to leeward.

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I actualy find that I need some kicker to power the sail up dowind, otherwise all the energy in the wind and gusts go to twisting the sail and bending the mast, before it gets transferred into power in the rig. some kicker holds the sail in the shape you want it to be in order to power up, just remember to blow it before gybing!!

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winging it View Drop Down
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Post Options Post Options   Quote winging it Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 12:47pm
Originally posted by alstorer

Ok, whilst we're on the subject- the floppy stayed rig of the Solo- what the hell is that all about?


Yes, and likewise the streaker, where they don't use much kicker either.
the same, but different...

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tack'ho View Drop Down
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Post Options Post Options   Quote tack'ho Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 12:57pm
Originally posted by Steve411

 

Another well-engineered unstayed rig. The main thing is that kicker tension is the key sail control as kicker tension, mast bend, sail fullness and leech tension are inextricably linked. You can't have a tight leech for pointing without flattening the sail off for example.

Ok here is the big difference with the CII rig: We do not use the kicker upwind even when it's blowing dogs off chains.  It is just snugged so the boom doesn't sky in tacks and has no tension in it when beating.  My shape control is the downhaul.  I would try to explain it but just go onto youtube and watch the explabation from Ian bruce or download the instruction video, link on the Byte website, he explains it much better.

Downwind, i have the worlds hardest leech, it's called the mast!! (thanks to Steve Cockrill for that one!)



Edited by tack'ho
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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: 12 May 09 at 12:59pm
Originally posted by winging it

Originally posted by alstorer

Ok, whilst we're on the subject- the floppy stayed rig of the Solo- what the hell is that all about?
Yes, and likewise the streaker, where they don't use much kicker either.

Both rigs without spreaders aren't they? If you haven't got spreaders then I'nm sure that rig tension becomes a whole lot less critical. I would guess that changes in rig tension have a minimal effect on mast behaviour, modified a bit by deck level control.
One advantage that immediately occurs to me is that low tension rigging effectively means that the lee shroud is slack on any kind of reach, which in turn means minimal disruption of the sail shape by the shroud. That's got to be a good thing...

Edited by JimC
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Post Options Post Options   Quote Isis Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 1:13pm
There are a lot of comments on the effectiveness of certain unstayed rigs - but the key point is that these are all found classes forced down the unstayed route by their rules. Have a think about what would happen if stayed rigs were allowed in these classes...
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Post Options Post Options   Quote tack'ho Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 1:30pm

mmmm yer I could have a telegraph pole...sorry streaker rig (who if only they weren't constrained by class rules could have a better section carbon mast) and go slower...(ooo yer and they could have a plumb bow as well to maximise waterline length,  and go really narrow, and have foils....damn those class rules!)

The point I have been making is sweeping statements such as 'stayed rigs good unstayed rigs bad' are a bit silly.  What needs considering is what do stays do? Can that be achieved in a more efficent manner? Do the comprimises in stayed rigs have more of an impact than the comprimises of unstayed rigs? etc.  In fact utimatley if you could build a unstayed mast light enough and stiff enough and control the degree of flexibilty over the length and in the desired planes well enough, you can get rid of your stays.

I might be sailing it, but it's still sh**e!
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Post Options Post Options   Quote tack'ho Quote  Post ReplyReply Direct Link To This Post Posted: 12 May 09 at 1:51pm
Originally posted by Daniel Holman

Originally posted by tack'ho

....... Now, a blank peice of paper with a unstayed shaped mast section designed to be controlled in the same manner as the Byte rig on a hull specifically designed for it......and if you can make it aimed at 70kg sailors.....that I would like to see.

The paper was particularly blank. Prob more a 75- 80kg person's boat right now, but smaller and bigger versions of the rig in the pipeline...

sorry meant to ask...what is this?



Edited by tack'ho
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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: 12 May 09 at 3:14pm
Originally posted by tack'ho

In fact utimatley if you could build a unstayed mast light enough and stiff enough and control the degree of flexibilty over the length and in the desired planes well enough, you can get rid of your stays.

Sadly suitable quantities of the appropriate specification of unobtanium are proving tricky to source...

I think I've seen 4 attempts at unstayed rigs in development singlehanders in recent years, and the score is three definitely not competitive and one possibly competitive... None have demonstrated an advantage.

Of course that's not to say its impossible. To my mind no-one has yet come up with what I regard as a really advanced modern single sail rig - or any non-spinnaker craft.

The new Byte rig is certainly a big improvement on what was there before, but I an yet to see an advance I consider equivalent to the prebent flex top skiff style rigs for two handed spinnaker boats. Of course those rigs suffer from the big disadvantage that they are rubbish with the boom squared off... The rig for spinnaker free craft is a very big design challenge indeed.
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