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Sailboarder
Joined: 10 Apr 2011
Posts: 656
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 Posted: Mon Aug 17, 2015 4:34 pm Post subject: |
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| adywind wrote: |
This is probably true for a fast racing longboard /don't know-never been on one/, but the slow boards with daggers that I sailed when learning the sport behaved differently . In less then 10 kts the dagger created nothing but drag slowing the board even more and making it drift downwind . Retracting the dagger and depressing the windward/upwind/ rail on the other hand was letting me maintain some speed and climb upwind. After I gained more confidence I started removing them regardless of the water gushing thru the gasket at speed. That's why my less then favorable opinion of daggers and later when shopping for a Windsup I didn't even look at those with . |
This is quite puzzling to me ! The exact opposite of my personal experience. I was out in very low wind last week and both my Kona or my old Sailboard would have been close to impossible to sail without the centerboard.
Were you a beginner last time you tried one? I've seen beginners trying to start already on a close reach, it doesn't work well. You need to have some speed to get the centerboard to grab before being able to sail well upwind, so it's easier to gain a little speed on a beam reach before closing tight on the wind.
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adywind
Joined: 08 Jan 2012
Posts: 665
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| Posted: Mon Aug 17, 2015 4:39 pm Post subject: |
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| techno900 wrote: | Using the proper technique, it's ALWAYS faster upwind with the dagger board down in any wind (1-30 knots). Over 20 knots, one may have to kick the dagger up a bit to keep the board from "turtling" (too much dagger lift).
Proper technique means leeward rail down, windward rail up. That's why most racing longboards have "hiking" straps. Usually, only one foot is in the strap, with the other foot placed as needed (sink the leeward rail in light winds or hold down the windward rail in stronger winds).
Even on a beam reach, you want to convert the lateral wind forces into forward momentum, and a dagger helps. As speed increases, the dagger is moved up and should be all the way up if planing with good speed (in the rear straps).
I have raced a windsup with a dagger and it is very efficient in light winds, but needs the dagger board down to make any real upwind progress. |
I want to see you using the "proper" technique when you don't have any power in the sail to lean against. You better start performing the old freestyle railriding trick then or it will be very funny. And btw I came to the technique you are describing all by myself while trying to keep my slalom board flat and planing longer in the lulls.
Here's what my upwind no dagger technique looks like, a bit exaggerated in this picture and one handed for show off 
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dllee
Joined: 03 Jul 2009
Posts: 5329
Location: East Bay
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| Posted: Mon Aug 17, 2015 5:36 pm Post subject: |
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Faster, and VMG, or upwind efficiency, are two different animals entirely.
Faster is boatspeed, best acheived off the wind, dagger up, and best in planing conditions with the hull up and planing, of course.
VMG is upwind and downwind efficiency. Not boat speed, but time it takes to go upwind or downwind.
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coachg
Joined: 10 Sep 2000
Posts: 3560
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| Posted: Mon Aug 17, 2015 11:05 pm Post subject: |
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| adywind wrote: | | I want to see you using the "proper" technique when you don't have any power in the sail to lean against. |
I think it would look something like this.
Coachg
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adywind
Joined: 08 Jan 2012
Posts: 665
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| Posted: Tue Aug 18, 2015 5:18 am Post subject: |
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| coachg wrote: | | adywind wrote: | | I want to see you using the "proper" technique when you don't have any power in the sail to lean against. |
I think it would look something like this.
Coachg |
Not exactly, but we are getting there. Nobody is railing the board on its leeward rail in this picture because there is not enough speed to get any lift from the dagger. The guys are just sailing flat holding their rigs in the classic 7 position with both of their feet across the center.
The wind strenght on the other hand is spot on of what I had in mind and now back to my original question: which way will be faster /and consequently point higher/ in such a light wind conditions ? Dagger down, riding flat in figure 7 position, or dagger up, railing the windward rail with front foot pointing forward and holding the rig upright and closer to your body with bent arms /a bit like in the picture below /?
I think the answer to that question will help ittiandro in his quest for finding the most efficient way of sailing /fastest/ in light winds.
And I can tell you right away that judging by the wake I'm going faster on my 110L AtomIQ and 7.5 Retro then those guys on their huge Konas and 8.5s??-they are spilling away too much wind and their daggers create too much drag IMO.
And why is everybody having their booms so ridiculously low are they going to ride waves in 40 kts after going around the corner ?! Too much old school stuff I guess.
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whitevan01
Joined: 29 Jun 2007
Posts: 607
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| Posted: Tue Aug 18, 2015 7:01 am Post subject: |
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| adywind wrote: |
This is probably true for a fast racing longboard /don't know-never been on one/, but the slow boards with daggers that I sailed when learning the sport behaved differently . In less then 10 kts the dagger created nothing but drag slowing the board even more and making it drift downwind . Retracting the dagger and depressing the windward/upwind/ rail on the other hand was letting me maintain some speed and climb upwind. After I gained more confidence I started removing them regardless of the water gushing thru the gasket at speed. That's why my less then favorable opinion of daggers and later when shopping for a Windsup I didn't even look at those with . |
well, you asked about longboards. all boards/boats with daggers/keels/centerboards act the same way. it's physics.
btw, if the wind is not enough to heel the board to leeward to go upwind, then one should weight the leeward rail to make it heel, just like one does in light wind with a boat.
always faster upwind with dagger down providing lift.
and yes, booms on dagger board boards a little higher than on a shortboard. this so one can hang their weight off the boom which also helps to heel the board to leeward.
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techno900
Joined: 28 Mar 2001
Posts: 4172
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| Posted: Tue Aug 18, 2015 7:31 am Post subject: |
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In light winds, under 5 knots, and NO dagger board, sinking the windward rail to promote upwind performance is a good idea. We all have done it, even on short boards when the wind dropped.
With a dagger in winds under 5 knots, keeping the board flat or sinking the leeward rail a little is best, but not the windward rail. I can't count the number of hours, 100+ I have spent racing in sub-planing winds, including Formula, competing and watching other sailors do there best to get moving as past as possible. The dagger is there for a reason, use it.
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konajoe
Joined: 28 Feb 2010
Posts: 517
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| Posted: Tue Aug 18, 2015 9:19 am Post subject: |
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Man, this discussion got off track! I helped with some lessons over the weekend. I saw a guy sliding through the water as ady described. I sailed over, and had a good hard look at his centerboard. "Is that centerboard up or down" It was up.
It happens all the time to folks not familiar with boards with centerboards. That sensation of sliding sideways was with the centerboard UP, not DOWN. You were confused on the position. It's hard to tell by looking at the knob while you are sailing if you're not familiar with the board. And as you said, you weren't.
| whitevan01 wrote: | | Heeling the board to leeward will cause the board to turn towards the wind and increases the effective waterline length, which causes the distance between the bow and stern waves to increase, thereby increasing speed through the water. |
Uh-oh. Here we go with mis-applying that waterline formula again. A board with it's centerboard down being sailed on it's leeward rail is capable of going WAAAAY faster than the answer that formula gives for maximum speed. Again, that keel boat max speed formula just doesn't apply to us.
But, when you rail a board to leeward, you make a leaner entry through the water. You effectively make it a narrower board, which cuts through the water better. The leeward rail down doesn't make the board turn upwind. When one rides with the centerboard down and leeward rail down, it rides perfectly straight. You will be able to point better with the rail down.
Now, if you sink the leeward rail back by the tail, that's a different story.
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cgoudie1
Joined: 10 Apr 2006
Posts: 2599
Location: Killer Sturgeon Cove
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| Posted: Tue Aug 18, 2015 9:55 am Post subject: |
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All this longboard and dagger board talk is giving me a rash. Where's my 7'9" OO. I'm taking it out for a spin Saturday. Dagger boards make great paddles when there's no wind. ;*)
-Craig
p.s. in displacement hull mode all the long boards I've ever ridden
were much faster to weather with the dagger board down, and my
feet in the beating straps (if there was enough wind). You can really develop some forward thrust pushing sidways
with your feet across the board. That would be with the board hull flat to
the water surface, not railed (well, maybe railed slightly).
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coachg
Joined: 10 Sep 2000
Posts: 3560
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| Posted: Tue Aug 18, 2015 10:47 am Post subject: |
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| adywind wrote: | And I can tell you right away that judging by the wake I'm going faster on my 110L AtomIQ and 7.5 Retro then those guys on their huge Konas and 8.5s??-they are spilling away too much wind and their daggers create too much drag IMO.
And why is everybody having their booms so ridiculously low are they going to ride waves in 40 kts after going around the corner ?! Too much old school stuff I guess. |
The red sails are 9.0, the orange 9.8 and the yellow 7.4 based on the sailor's weight. They appear to be riding the boards flat but I can promise you they are applying pressure through their back foot toes to drive upwind off the centerboard. The guy out front in the picture is Andy Brandt who cut his teeth racing longboards in light wind. I'll tell him that you think you are faster upwind with your Atom 110, 7.5 Retro and that you feel his boom is too low. That ought to bring on a great laugh.
Coachg
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