^+1

Franco: Is this the same sail where you "shortened" the battens ?
If so, why would "rotation" EVER be an issue...

why are you reverse engineering everything and modifying ALL ??

hard to follow and we know you mean well !!

When I got back into windsurfing 6 years ago, I found the whole varying mast & sail curve issue a pain in the ass. I didn't want to be locked into one sail manufacturer, so I decided to only purchase constant curve masts (Naish, North, KA & Loft) and hence have a good selection of constant curve sails I could use with them. Hence apart from a 6.0 Severne Gator, I don't or haven't owned any Severne, Maui, Gastra, HSM or Neil Pride sails. This has not limited my sail choices as I have owned Naish, Loft, KA, North and Gun sails.

My recommendation is to choose a bend curve range (either constant, flex or stiff) and stay there.

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joe windsurf said..
^+1

Franco: Is this the same sail where you "shortened" the battens ?
If so, why would "rotation" EVER be an issue...

why are you reverse engineering everything and modifying ALL ??

hard to follow and we know you mean well !!

No, the sail I am talking about, as I said in my post, is the N.P. Garda 6.2. I never modified it. I didn't need to, because it is an excellent sail. It works and rotates well as it is, even with a full d/haul and, unexpectedly, it rotates even better with a mast tip extension. This is why I wrote this post and I ventured an explanation.

So I am not doing " reverse engineering" on everything and modify ALL. I only do it when I have reasons. Sometimes I am right, sometimes I am wrong. In fact, my at times heated discussions on various Forums have given me food for thought and in the process I have changed my views on certain issues.

The sail I had modified was the Sailworks Race 5.6. A much younger sail than the Garda, but, unlike it, it had a lot of room for improvement, with some .. creativity and... “ reverse engineering”, but I was right, because the sail works a lot better and gained more power after the modification.

My “reverse engineering” and my way of looking at things may leave somebody skeptical or make it difficult, as you say, to follow me..

This is perhaps because some people expect a sort of “ scientific” consistency in the way we speak ( and practice) windsurfing, underestimating perhaps that our sport, if it obeys to certain basic laws of physics, is in many respects also an art, not always conducive to a precise ( or consistent set of rules).
It has a lot of variables, some subjective, but none the less important.

Each one of us suits windsurfing to his/her own individual needs, tastes and physical capabilities and in doing so we may be frowned upon by those who ..go by the book and think we are wrong .

In reality, unless somebody claims to be able to sail straight into the wind (!) or that the most efficient point of sail is when we are in the RUN course, we may ALL to a certain extent, be right ( or wrong).

One can learn the “ rules” of painting, but the true geniuses,( the Leonardos or other) often, if not always, break them. ( I am not implying that I am..a windsurfing genius, though!) . Stated otherwise, a general may have well planned strategy in his head to reach his objective , but he will eventually have to make tactical modifications based on the contingencies of the battlefield.

Francone

Generally, when you replace the flex top with a CC, your draft is back and shallower, your leech is tighter.
The first is not too bad, as draft back has good low end, while shallow can handle some amount of wind. The tighter leech is not a huge problem, because a CC mast bends more at the bottom, so more downhaul allows for loose leech, but then the draft moves back some more.
So, rig it not too loose in the leech. The softer bottom section will flex and compensate for the lack of leech looseness.

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forceten said..

KA, I can offer no info, nor find what the mast curve is .

Did you look at the Unifiber chart? KA is there.

all i am saying is it feels like a lot of effort with unknown results
too much work for me :-)
good luck Francone - will stay out of this discussion :-)

joewindsurfer.blogspot.com/2008/07/masts.html

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N1GEL said..

forceten said..

KA, I can offer no info, nor find what the mast curve is .

Did you look at the Unifiber chart? KA is there.

Go to the KA website...it is there. 13.5%

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mr love said..

N1GEL said..

forceten said..

KA, I can offer no info, nor find what the mast curve is .

Did you look at the Unifiber chart? KA is there.

Go to the KA website...it is there. 13.5%

I did look at the KA, site, I did not see the 13.5, it however does not have the 1/4 and 3/4 figures. So the 13.5 is a partial picture. Even So using 13.5 , that puts them into barely CC Flextop.
with that I see not reason why the KA , should not perform adequately on a HSM, sail. What I find curious, is that all the KA masts, RDM, SDM and different carbon content have the same 13.5. So it's not a CC .

i use a HSM mast on my Simmer, it works fine. Simmer , esp the RDM are flex top, very similar to the HSM.Its roughly 14.1.

Since neither KA nor Simmer were the question , this is only pertinent , if they were a CC , unfortunately they are not. Both have flex top bias to say the least.
These are the things that dictate mast feel
1. Overall stiffness
2. The ratios between 1/4 1/2 3/4 bend points... weight hung from middle and all that math
3.the carbon content.
4. The carbon orientation . More zero axis fibers= better reflex.
its possible to have a softer mast, that feels stiffer because of carbon orientation. NoLimitz being one with the Sumo.

I find this whole thread offensive and believe it should be deleted by the moderator.
Are you guys sadomasochists? Something kinky is going on.
Just get a sail and mast that suit each other.
Buy second hand if necessary.
I've got a headache.

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forceten said..
>>big edit<<

These are the things that dictate mast feel performance in a sail
1. Overall stiffness
2. The ratios between 1/4 1/2 3/4 bend points... weight hung from middle and all that math
3.the carbon content.
4. The carbon orientation . More zero axis fibers= better reflex.
its possible to have a softer mast, that feels stiffer because of carbon orientation. NoLimitz being one with the Sumo.

1. for sure
2. for sure, but, this is expressed as the %. The deflection figures themselves are irrelevant/useless info because you have the % difference and the MCS stiffness.
3. 'Reflex' is purely determined by the weight and stiffness of the mast. The rest of that 'reflex response' stuff is marketing BS.
4. Total rubbish!

Where do you get this stuff from? Marketing brochures? Have you ever done any MCS or IMCS testing yourself?

Select to expand quote

Sparky said..
I find this whole thread offensive and believe it should be deleted by the moderator.
Are you guys sadomasochists? Something kinky is going on.
Just get a sail and mast that suit each other.
Buy second hand if necessary.
I've got a headache.

Is some invisible force making you read this..this
and the entire thread?

i will grant that it's not on topic as such

Select to expand quote

sailquik said..

forceten said..
>>big edit<<

These are the things that dictate mast feel performance in a sail
1. Overall stiffness
2. The ratios between 1/4 1/2 3/4 bend points... weight hung from middle and all that math
3.the carbon content.
4. The carbon orientation . More zero axis fibers= better reflex.
its possible to have a softer mast, that feels stiffer because of carbon orientation. NoLimitz being one with the Sumo.

1. for sure
2. for sure, but, this is expressed as the %. The deflection figures themselves are irrelevant/useless info because you have the % difference and the MCS stiffness.
3. 'Reflex' is purely determined by the weight and stiffness of the mast. The rest of that 'reflex response' stuff is marketing BS.
4. Total rubbish!

Where do you get this stuff from? Marketing brochures? Have you ever done any MCS or IMCS testing yourself?

Select to expand quote

sailquik said..

forceten said..
>>big edit<<

These are the things that dictate mast feel performance in a sail
1. Overall stiffness
2. The ratios between 1/4 1/2 3/4 bend points... weight hung from middle and all that math
3.the carbon content.
4. The carbon orientation . More zero axis fibers= better reflex.
its possible to have a softer mast, that feels stiffer because of carbon orientation. NoLimitz being one with the Sumo.

1. for sure
2. for sure, but, this is expressed as the %. The deflection figures themselves are irrelevant/useless info because you have the % difference and the MCS stiffness.
3. 'Reflex' is purely determined by the weight and stiffness of the mast. The rest of that 'reflex response' stuff is marketing BS.
4. Total rubbish!

Where do you get this stuff from? Marketing brochures? Have you ever done any MCS or IMCS testing yourself?

where from.. 1-4. Your # 2.. What are saying ? The % comes from the math..without posting to each person how to determine all this.
There
is a sail designer in Hawaii, His name is David Ezzy, 1--4.

By marketing.. you mean the printed specs and associated descriptions.? Some specs are dubious and as are the printed , to market a mast that is not quite CC into a bracket that one size that fits most, for sales.

no I have never tested masts. Nor do I feel compelled to. I have never taken a Mazda rotary engine apart, but can explain how it works.

OP

check the HSM
for Jeffs reply.

or the Gun mast is CC it will be ok.

does not address the tip extension

Select to expand quote

forceten said..

sailquik said..

forceten said..
>>big edit<<

These are the things that dictate mast feel performance in a sail
1. Overall stiffness
2. The ratios between 1/4 1/2 3/4 bend points... weight hung from middle and all that math
3.the carbon content.
4. The carbon orientation . More zero axis fibers= better reflex.
its possible to have a softer mast, that feels stiffer because of carbon orientation. NoLimitz being one with the Sumo.

1. for sure
2. for sure, but, this is expressed as the %. The deflection figures themselves are irrelevant/useless info because you have the % difference and the MCS stiffness.
3. 'Reflex' is purely determined by the weight and stiffness of the mast. The rest of that 'reflex response' stuff is marketing BS.
4. Total rubbish!

Where do you get this stuff from? Marketing brochures? Have you ever done any MCS or IMCS testing yourself?

sailquik said..

forceten said..
>>big edit<<

These are the things that dictate mast feel performance in a sail
1. Overall stiffness
2. The ratios between 1/4 1/2 3/4 bend points... weight hung from middle and all that math
3.the carbon content.
4. The carbon orientation . More zero axis fibers= better reflex.
its possible to have a softer mast, that feels stiffer because of carbon orientation. NoLimitz being one with the Sumo.

1. for sure
2. for sure, but, this is expressed as the %. The deflection figures themselves are irrelevant/useless info because you have the % difference and the MCS stiffness.
3. 'Reflex' is purely determined by the weight and stiffness of the mast. The rest of that 'reflex response' stuff is marketing BS.
4. Total rubbish!

Where do you get this stuff from? Marketing brochures? Have you ever done any MCS or IMCS testing yourself?

where from.. 1-4. Your # 2.. What are saying ? The % comes from the math..without posting to each person how to determine all this.
There
is a sail designer in Hawaii, His name is David Ezzy, 1--4.

By marketing.. you mean the printed specs and associated descriptions.? Some specs are dubious and as are the printed , to market a mast that is not quite CC into a bracket that one size that fits most, for sales.

no I have never tested masts. Nor do I feel compelled to. I have never taken a Mazda rotary engine apart, but can explain how it works.

Select to expand quote

forceten said..

Sparky said..
I find this whole thread offensive and believe it should be deleted by the moderator.
Are you guys sadomasochists? Something kinky is going on.
Just get a sail and mast that suit each other.
Buy second hand if necessary.
I've got a headache.

Is some invisible force making you read this..this
and the entire thread?

i will grant that it's not on topic as such

My point is that sometimes things don't have to be that complicated. Get a sail that suits the mast or vice versa. Don't put too long an extension on it (30cm plus), don't use a tip extension (I get spam emails from a guy trying to sell me these), and maybe reconsider whether you need a 8.0 on a windsup? I find a larger sail on a non planing board just produces more drag. Wouldnt a 6.0 or 7.0 do the job?
i suppose I'm a windsurfing minimalist, don't get me started on helmets, gloves, knee straps, elbow straps, life jackets, booties, board nose protectors, boom guards................

And forceten, what's with the cat looking like a shark business, bit weird buddy.

Select to expand quote

Sparky said..

My point is that sometimes things don't have to be that complicated. Get a sail that suits the mast or vice versa. Don't put too long an extension on it (30cm plus), don't use a tip extension (I get spam emails from a guy trying to sell me these), and maybe reconsider whether you need a 8.0 on a windsup? I find a larger sail on a non planing board just produces more drag. Wouldnt a 6.0 or 7.0 do the job?
i suppose I'm a windsurfing minimalist, don't get me started on helmets, gloves, knee straps, elbow straps, life jackets, booties, board nose protectors, boom guards................

+1

Select to expand quote

Sparky said..
And forceten, what's with the cat looking like a shark business, bit weird buddy.

Umm

I second that!