VANCOUVER ISLAND WINDTALK • sail size
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sail size

Posted: Tue Dec 07, 2010 5:41 pm
by rich
Hello,

I have a 105L board and 5.5 sail and weigh 165lbs. The board is hard uphaul on so I have to waterstart.

I have not been able to use the equipment often due to wind being around 17 knots on most windy days north of Nanaimo.

What is the best sail size to use for such condition so that I can waterstart?

What is the next bigger sail size and also the next smaller size to complete the sail set?

Thanks,

Rich

Posted: Tue Dec 07, 2010 6:19 pm
by rvanderbyl
For what it's worth....I'm the same weight as you and have a 104 that I use with a 5.4 a lot of the time. 17 knots is pretty light for that combo. A good size for you in that range might be might be 6.0 to 6.5 or even 7.0. If your looking to add to your quiver a 6.2 might be a good jump up from ythe 5.5, IMHO.

Posted: Tue Dec 07, 2010 7:37 pm
by rocdoc
Rich - With your weight and board you should be able to waterstart easily with 5.5 in 17 knots. I'm 205 and only need about 12-15 knots to waterstart a 95L with 5.5 sail. Most of it is technique and practise.

Posted: Tue Dec 07, 2010 7:41 pm
by rocdoc
Rich - Should have also mentioned at 205 lbs I would need more like 15-20 knots to get planing.

Posted: Wed Dec 08, 2010 8:58 am
by nanmoo
Don't go bigger than 6.0, it's not fun unless you have flat water.

6.0 gets me going on my 91L in 17 knots and I weigh 185lbs.

Posted: Wed Dec 08, 2010 9:21 am
by more force 4
This is surprisingly accurate, especially if you carefully read the 'notes':
http://jimbodouglass.blogspot.com/2010/ ... nline.html

When I type in 165 lbs and 17 knots (you can type wind speed directly into the green box, as the table shows 16 and 18 knots only), it suggests you should be happy on a 5.9 to 6.0. Learning to waterstart and plane in this much wind with a 5.5 is possible, but you'll be slightly underpowered which makes it much more difficult. Its actually much easier to be a bit overpowered than underpowered when learning waterstarts. Experienced sailors learn to get the board going with smaller sails, but the right technique is crucial. On the other hand, the table says you should only need about 18 knots to be nicely powered on the 5.5 (enter sail size in pink box); just a few knots makes a huge difference in this wind range. Modern gear is also much more tunable and tolerant of being either over or underpowered so you'll find people happy even way outside the suggested 'sweet spot' of these tables.

Posted: Wed Dec 08, 2010 10:39 am
by downwind dave
if you are building a quiver around a 5.5 you probably want a 6.5 and a 4.7. a less ideal but practical way to build a quiver is look at the mast your 5.5 is on, and how big you can go without having to buy a longer mast. :wink:

Posted: Wed Dec 08, 2010 11:08 am
by KUS
Pretty wide open questions there, dood.
5.5 will most certainly be a 430, KA Koyotes go up to 6.6 with that length, no probs and as your sail size goes up I would suggest to have larger size gaps, 5.5 to 6.6 sounds about right to me, kinda like 5.8 to 7.0 or even 7.5 whereas you'd go from 4.2 only up half a meter to a 4.7 usually.
Also is the 5.5 a power sail or a wave? This size is usually a cut off depending if you are a heavier person to go from a wave to a power sail, I make the switch to power at 5.3 for around here. :idea: As for going down a sail size usually a 5.5 matches with a 5.0 not a 4.7 unless the 5.5 is at least a wavesail, a 4.7, 5.3, 5.8 is common.

Getting more efficient doing your waterstart will result in lower wind to be sailable. Try kicking with your front leg and throwing the mast forward, pump/row the sail once on the waterstart to get your body out of the water easier. Also being able to sink the board's tail is easier on a wave and smaller board allowing you to step up more easily.
You must be active and develop the waterstart movement in a fluid motion. If u are getting your ass dragged through the water waiting for the wind to pick u up you might be there a while and it doesn't necessarily relate to your sail size. Typically if the wind CAN pick u up while dragging your ass and you don't need to do much athletically to get up, then you'll be overpowered on the subsequent runs :roll:

Hope u actually read this feedback from the others taking the time to provide u advice, too often these wide open "how do you windsurf" posts are a one-timer poster :roll: :?

Posted: Wed Dec 08, 2010 1:04 pm
by winddoctor
Welcome to the forum, Rich!

My input relates more to the waterstarting aspect.

Morley's post has some very good info for you, as do the others. In the mean time, waterstarting a 5.5 on a 105 L board at your weight in a true 17 knots should be completely reasonable as long as you keep in mind a few key things:

1. When you are flying the sail, keep the tail of the board close to you (keep back leg bent). DO NOT waterstart with both feet on board unless it's cranking. You want to stay vertical in the water, not leaning backward.

2.Keep the rig as upright as possible (don't pull rig over you). In lighter air, try to tuck your head under the boom and keep that back foot pulling the tail close to you as you power the sail up and kick with the front foot. Use your hamstrings to bring the tail under you. This brings you to the rig and uses the mast foot and board buoyancy to help lever you up and out.

3. Bear the nose off the wind to increase your chances of getting up; steer/head upwind if you feel too much pull. Find that happy place in the middle where you have enough power and control. That's the key.

At 200 pounds, I regularly sail a 5.3 or even 4.7 on a fast-planing, 100 L freestyle board in just under or about 20 knots. I tend to like to sail more powered up than this, but my point is that once you develop efficiency you'll have the 105 ripping with a 5.5 in 17 knots. My 95 L Freestyle Wave board needs a 5.6 for me to sail powered up enough to get little jumps and plane around in 17 knots.

Good luck!

Posted: Wed Dec 08, 2010 1:59 pm
by nanmoo
winddoctor wrote:At 200 pounds
:shock: :shock: :shock: :shock: :shock:

Posted: Sun Dec 12, 2010 2:18 pm
by mortontoemike
The formula that is in the spreadsheet MF4 posted is:

Sail Size = (1.34*body wt in Kg )/windspeed in kts

Does anyone know where the factor 1.34 comes from or is it empirical?

Posted: Sun Dec 12, 2010 5:36 pm
by more force 4
write to James, he'll gladly tell you I'm sure

Posted: Sun Dec 12, 2010 5:46 pm
by Geoffy
The resultant graph is completely incorrect for me except maybe in the very lowest windspeeds, no way I am on a 3.1 in 30 kts where I typically use a 4.0, nor would I ever be on my 4.0 in about 23 kts as this recommends. And I am not a "power sailor." Dangerously simplified imho.

Posted: Sun Dec 12, 2010 6:12 pm
by KUS
those tables don't take into account variation in board volume .....or fin size, waves, weeds, anything affecting planing ability

It appears by the lack of feedback our open-ended question friend Rich has likely long lost interest :roll:

Posted: Sun Dec 12, 2010 8:54 pm
by JL
Light wind water start: Keep the forward hand on the mast instead of the boom ... The closer to the mast base the more leverage provided by the rig !!! 8)