When I go windsurfing it is normally 15 to 20 knotts and i use a 7.5m Sailworks sail..It feels really stable.

On the weekend out in 25knotts or so..Rigged up my 6.5m North and it felt really unstable compared to my 7.5m.

Is there such a thing as a more stable sail? Or the bigger the sail the more stable it is?

I was out today in 20-30 knot winds and I used a North 5.3 sail and was perfectly powered up. I would be way too overpowered on a 6.5 sail in 25 knots of wind. Hope that helps.

6.5m sail is pretty big for 25kn. I'm usually in 4.7/5.3 mode by then.
A couple of things to try is the favourite - More downhaul.
Second one you can try is let some outhaul off. This can help the leech twist and sail de-power which will stop the sail feeling so "twitchy" and unstable.

Before you start 'gear panicking' at any point over the last weekend we had 15-30knts , so that may account a bit of your 'unstable' issue..the wind was very unstable and super gusty, that may have something to do with what you were dealing with.
Where as 15-20knots is very stable and narrow wind range so yes, any decently rigged sail should feel stable in that range, so I wouldn't be panicking just yet, think we all had our own gust battles at different times this weekend.

Firstly to answer your question of more stability. More battens and / or Camber induced sails are the most stable. That's why the slalom guys can use a 7.0 in 25kts plus while the wave / freeride group are using 5.0 or less.

For what its worth a 6.5 non cambered freeride type sail is very big for 25kts. And if you were sailing anywhere in SEQ over the weekend not only was it Gusty, but i reckon there were 15-20 degree swings in direction as well.

I was using a 4.2 nicely powered in the bay on the WE gusting to 30

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DAM71 said..
Firstly to answer your question of more stability. More battens and / or Camber induced sails are the most stable. That's why the slalom guys can use a 7.0 in 25kts plus while the wave / freeride group are using 5.0 or less.

For what its worth a 6.5 non cambered freeride type sail is very big for 25kts. And if you were sailing anywhere in SEQ over the weekend not only was it Gusty, but i reckon there were 15-20 degree swings in direction as well.

Agree with this. I will use a 7.3 cam sail in wind up to about 28knts. So, depending on the type of sail, I don't think a 6.5 is unreasonable for those conditions.

Without knowing what sail you were using, I'd hazard a guess that maybe your rigging wasn't so good if the sail felt twitchy. Twitchy usually happens because the sail is rigged too flat/tight. You could try less out haul and more down haul to induce better "leech twist", which helps the bigger gusts "spill" off the sail. You might also have the wrong mast for that sail, this too can essentially cause the sail not to twist off nicely in the leech.

I'm only guessing at what might be going on, but these are a couple of easy things to check. The North sails I've used were never twitchy... Generally speaking Norths are great sails IMO.

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kpb said..
When I go windsurfing it is normally 15 to 20 knotts and i use a 7.5m Sailworks sail..It feels really stable.

On the weekend out in 25knotts or so..Rigged up my 6.5m North and it felt really unstable compared to my 7.5m.

Is there such a thing as a more stable sail? Or the bigger the sail the more stable it is?

Hi kpd...was it on different days that you tried the sail .the reason I ask ...did you measure the wind ? As you have to have a pretty good eye or years of watching the wind and spray to know..what sail to rig eg ..does a 20 knot day look like a 27-28 knot day ..
It just sounds like you where either over powered or under ...I would recommend a wind metre ..it's saves rigging twice.
if it was 25 knot solid , I would rig a 6.0.slalom or 5.5 .wave.

yes race sail have more stability.

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kpb said..
When I go windsurfing it is normally 15 to 20 knotts and i use a 7.5m Sailworks sail..It feels really stable.

On the weekend out in 25knotts or so..Rigged up my 6.5m North and it felt really unstable compared to my 7.5m.

Is there such a thing as a more stable sail? Or the bigger the sail the more stable it is?

Sail stability can have a lot to do with how you rigged the sail, sounds like the Sailworks Retro 7.5m is rigged correctly whilst the North is not. Questions that come to mind are: Age of sail, mast compatibility, boom outhaul and rig tension.

Thank you for your replies. ..

I think i may have rigged the sail too flat...I did really pull the outhaul as far as i could...When i am rigging the 7.5m sail i dont pull the outhaul that tight...

I will be conscious of this in future...

I also haven't matched the sail to the mast since i snapped the top half of my North mast 1 year ago...

The sail is also pretty old so might have to make a case to the houshold minister for finance for a new rig..

The more outhaul, the flatter the sail, the less power it has... which is what you want in this case.

Dear finance minister. It has been proven that a new sail has a 20% greater wind range than the old sails and this results in a 30% happier husband. Last years models are now on special so there are excellent savings. Please approve this essential budget request.

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Piv said...
Dear finance minister. It has been proven that a new sail has a 20% greater wind range than the old sails and this results in a 30% happier husband. Last years models are now on special so there are excellent savings. Please approve this essential budget request.

Haha...thanks Piv thats great