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PostPosted: Fri Apr 10, 2015 2:59 pm 
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I am used to using wind telltales on the stays or maybe atop the mast rather than on the sail itself like Hobie configures it. I wonder how Hobie kayakers make out with the stock config, or if they add more. I have the inflato version of the Hobie sail which actually has stays to mount my telltales, sometimes telling a different "tale" than the sail mounted ones.

The Hobie manual says to sheet things to keep both streamers stretched out. I'm gonna suggest to always stall (or ignore) the windward streamer. Here is a writeup for larger boats that suggests you should usually more or less stall the windward streamer (under "steering tails") http://www.wb-sails.fi/Portals/209338/n ... tales.html . This is because most lift comes from the leeward surface which should not be compromised for the inherently suboptimum windward shape.

But I come from a different perspective... protecting the kayak from overload by biasing toward the sheet-out end of the range. I normally have wildly shifting apparent wind, either from upwind ground clutter or from ocean swells slapping first the bow then the stern around. It is clumsy to fight this with the Hobie tiller, so sheet we must.

A further initial observation is that the stock stall indicators seem to lag behind my added stay telltales. With the apparent wind wildly oscillating, by the time the sail indicators have stabilized into a reading, that is already ancient history... especially the stall bubbles seem sticky and resist being formed or popped. Isn't it better to sheet based on stay indicators or even reading cat's paws on the water to either protect from a gust or optimize over AVERAGE wind direction, letting sail tufts fall where they may?

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PostPosted: Sun Apr 12, 2015 9:53 pm 
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Good post!

I use the telltales all the time - I have added a wind direction streamer to the top of my mast(s) but this can get wrapped around the mast due to roller furling/unfurling, especially if I have dipped it in the drink when putting the mast up. It is just a simple piece of recording tape pulled out of an old audio cassette and tied on - easy, cheap, floats in the breeze well and I have loads more where that came from if & when it wears out.

As to the telltails on the sail - I have two sorts on my two sails - one type are woollen thread streamers, the others are like ribbons. I have added a second set of woollen ones to that sail because the original ones were set higher up on the sail and had a tendency to catch on the panel seam and hang up.

Either way I have noticed two particular things about the telltales - one is that the wind is almost never particularly consistent from the perspective of these little boats; in other words it is rare to be able to maintain the same course and heeling angle and apparent wind direction for more than short periods at a time so the telltails will be constantly shifting and telling a different story. This is fine - it is all part of the challenge of sailing these boats - but it does mean you need to be very responsive to the wind and boat to be able to optimise the sailing performance of the sail as indicatred by the telltails. As a a result, when I am sailing I am constantly tweaking the sheet and rudder and my weight to try to keep the telltales streaming in the right direction.

The second thing is that the excessive (if I can call it that) bending of the standard mast really plays havoc with sail shape and consequently the way that the telltales 'indicate'. Recently I 'upgraded' to a carbon fibre mast that I put together using two tubes bought from a local fishing rod manufacturer; this is much stiffer than the standard alu mast and seems to have made a significant difference to the performance of the sail and the telltales are far more consistent in their readings. I have no basis for testing this theory (because I have nobody to sail 'against') but I believe that the sail delivers better performance on the carbon fibre mast than on the stock mast simply becase the foil shape is so much better - it certainly the boat is a lot more twitchy in terms of heeling which I put down to there being less flex in the mast to absorb/spill gusts and the sail shape looks a whole lot better in stronger breezes/gusts.

Personally I am happy to try to keep both telltails streaming aft in the 'approved' fashion - I am sure that in bigger/higher performance boats with fancier sails and over longer distances this probably makes a significant difference but for my part I am usually happy enough to be enjoying the sailing experience (as opposed to pedalling/paddling) rather than worrying too much about whether or not I have really tweaked my sail to the optimum.


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PostPosted: Sun Apr 12, 2015 11:45 pm 
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stobbo wrote:
It is just a simple piece of recording tape pulled out of an old audio cassette and tied on - easy, cheap, floats in the breeze well and I have loads more where that came from if & when it wears out.

Thanks; I was at a loss to think of something floaty enough to stay above the sail at mast top. Not sure of the best length for these things.

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PostPosted: Wed Apr 15, 2015 3:02 am 
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A 'thread' out of one of those woven poly tarps also works well and it lasts a bit longer too...


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PostPosted: Wed Apr 15, 2015 9:03 am 
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Tell Tails are used for a variety of wind indications.

Up high on the top of the mast or on a support stay (shrouds, forestays and bridles on catamarans), would be free to indicate apparent wind direction and undisturbed by the sails.

In the body of the sail indicate air flow over the sail surface.

On the leech of the sail help to indicate under or over sheeting as well as sail twist.

We simply place the basic sail body ones as a starter. These are the most common used in sailing. I like the leech tails and always have a free swinging wind indicator if I'm racing. I have a couple of diagrams that might help. Designed for Catamarans, but really similar.

How to place them:
Image


How to use them:
Image

The basics are to try and get both standard tells flowing. I would rather see the windward one stall than the lee side. Sheet out or change course until they flow. Then sheet in a bit.

The upper 3rd of the sail is a good location for "leech" tell tails. If you sheet too hard the tell tail will wrap to the lee side. Not sheeting hard enough and the tell tail flows straight aft. The right sheet tension typically causes the tell tails to flow aft then wrap to lee and repeat... alternating. Very difficult to get it all flowing correctly on a Kayak sail due to the limited tension and sheeting controls and no traveler. Catamarans have battens, downhaul, outhaul, and travelers on the sheeting systems... all work together to trim properly for different points of sail (directions you are sailing compared to the wind).

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PostPosted: Wed Apr 15, 2015 1:49 pm 
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I would like to get some telltales/tails to multitask in supporting "sailing by the lee" (leech tells?). It's a new sensation to me for jibe/gybes to be so forgiving; without a boom you can so easily just hand the sheet to one side or the other.

Image

mmiller wrote:
The basics are to try and get both standard tells flowing. I would rather see the windward one stall than the lee side. Sheet out or change course until they flow. Then sheet in a bit.

Thanks, although I seem to have a mental block on the diagrams just above that comment... horizontal or vertical view? Grey tell is the opposite side or alternate position of this side?

Also for the comment to make sense, I suppose the sail is flapping loose to get both to flow. If you had both flowing with a proper belly pulled, then I would sheet OUT a bit rather than IN to slightly favor the leeward tell and get a better force vector angle.

Image better than Image

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PostPosted: Thu Apr 16, 2015 9:26 am 
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Both of my diagrams are only on the weather side. Does not indicate the lee side.

Love the gif versions you posted. Nice.

I think you want the lee side less stable. Disregarding the tell tails, you sheet out until the sail luffs and sheet back in until that stops. Then use tell tails for finer adjustments.

Proper settings create a vacuum on the lee side, so makes sense its flow is less stable.

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PostPosted: Thu Apr 16, 2015 12:05 pm 
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I have never really understood the leech tell tails before... now I do! Thanks Matt 8)


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