Sail Change
Jonathon McMullan
Hi All,
Wouldn't that be akin to requesting that the Opticlass get a bigger rig just so I can sail one?
Plus I just bought a new sail so I don't really want to have to turn around and buy a new one just to have the required quiver of sails to be competitive across the board. Personally I'm not complaining about power after having survived the Hamilton Weather Bomb. Just my thoughts.
Jonathon M
Sent from my Transformer Prime
Andrew Brown
I am out of the class for now but think it could be quite cool to see
square tops.
One question for the sailmakers out there, Derek etc - could this
"extra" sail area be added to an existing sail?
Cheers
Andrew Brown www.forceracing.co.nz
Ph (+64) 9 4823 470
Mobile (+64) 27 222 5 159
28 Seon Place
Birkdale
Auckland
NZL
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Gavin
I disagree with Benny that a larger sail would make a larger sailor more
competitive in the light, especially not without severely disadvantaging
a smaller sailor in medium winds upwards. Someone like Katie will still
have the advantage of carrying 20kg less weight. Just like Phil will
always have the advantage of being several feel taller than myself. If
that was really the issue here, we would make smaller sailors carry a
lump of lead and have adjustable racks like the 9ers to account for how
tall people are.
It is mentioned that when the wind is up we are throwing away power
anyway, so having a square top will just twist away. While this may be
true upwind, it certainly isn't downwind and I don't think any of us
have trouble with these boats upwind... I wonder, with this "unlimited"
square topped main, how it is intended for smaller sailors to keep the
bow out of the water when sailing downwind in the heavy? These "cool"
classes that we are being asked to copy all carry gennikers which lift
the bow and never sail flat off. Also, having a larger main will mean
smaller sailors will have to depower a lot sooner and will struggle to
be competitive in anything other than light winds. I think it's simple
that if you are heavy enough to keep the leech tension on a square
topped main, you will sail away from someone who isn't.
I also wonder whether it is wise to make changes to the rig, when the
class has almost started towards a one design rig with such a large
number of people opting for the c-tech mast and norths sail combo.
Even if we do change to a square top, I think leech measurements are
essential to give a standard sized sail, rather than making it
unlimited. But I also think that changing the sail will put off people
like myself who have recently invested in a new sail and will create an
arms race for at least several years until the fastest sail design is
rediscovered. This can be compared to what we have currently, where a
technora sail can be purchased for $1400 and will stay competitive for
the foreseeable future.
Safe to say I am currently against changing rules regarding the sail and
even more against the current wording for doing so, especially if this
is intended to go through immediately - which with the current wording
it is! I could still be swayed and will be very interested to hear what
Derek has to say on this, among others.
Gavin Auld
Matthew Lovett
I tend to agree with both Gavin and Jonathon.
If there is an argument that a bigger sail is required to make the boat more
competitive for a heavier / taller skipper... surely a shorter / lighter
skipper (or group of skippers) could argue for a smaller sail.., (Laser 4.7
style). I´m playing the Devil´s advocate here but I don´t think a motion to
introduce a smaller sail would find a seconder !
The boat currently suits a particular size range of sailors, just as the
Finn suits a particular (different) size range. Why shift?
Matthew Lovett
3.7 #371.
Mark O'Brien
Hi all
I am keen to look at the idea of changing the 3.7 sail rules to allow a square top design. However, I think there still needs to be some regulations on the girth measurements, therefore will not be supporting the current proposal.
With no girth regulations sails will get wider as soon as they leave the boom and go higher after leaving the mast. Both would look ugly. The situation may arise where people own multiple sails and will choose the one to use for the regatta based on the forecast. I agree with Gavin that we need to continue to have sails that are practical in all conditions and stay competitive for the foreseeable future.
I think there also needs to be trials before a proposal is approved.
In developing sail rules we should be aiming for sails that
*Make the boats look good and exciting to attract prospective owners
*Make the boats fun and exciting to sail
*Have a reasonable lifespan (at least 5 years)
The current sail design does looking a little dated next to other classes (like the Javelin) that have the square top main.
I have come up with some rules (listed below) that should produce sails that meet the above criteria.
The main changes to the current rules are
*Remove the three current sail section rules and replace with one.
*Remove the 4 girth measurements and replace with one, which would be a lot quicker to measure. 1670mm at the mid leach point.
*Keep the current leach measurement and also use this length to restrict the foot depth. (no one ever has sails with foots 5900 from the head).
The other measurements (eg foot and luff length) are restricted by the current mast and boom rules. All current sails should fit these rules (except for some foots that may need a nip and tuck). Both of my fyfe sails have a girth at the mid leach point of 1660, so the bottom half of the sail would stay the same (they are quite vertical below this point, above this point the girth reduces rapidly). So possibly the current sails could be re-cut to have an extra triangle sewn on the back.
I have estimated that these rules would allow for a head of 900mm, currently they’re around 450mm. It would provide an extra 0.4-0.5 square meters of sail (5-6% more), which I think still will be manageable on the flat off, make the boats more exciting to sail in a greater wind range and would result in more reaches that are wiring reaches.
I will be interested to hear what any sail makers have to say on this discussion.
Regards
Mark
12. Sails
a. Sails shall be measured in conjunction with the ISAF Racing Rules and ISAF Equipment rules of sailing. The Class rules shall take precedence where there is any conflict.
b. Class Insignia and numbers are to be as shown on the sail plan.
c. Sails may be made from any material capable of being folded back onto itself without any permanent damage. Primary reinforcement may extend a maximum of 320mm from each corner of the sail. Multiply sails are allowed, but double-surface or inflatable sails are prohibited.
d. Only one sail may be used in any contest or series of races, except with the permission of the Race Committee controlling those races.
e. Sails shall be endorsed with measurer’s signature and date when found to measure correctly.
f. Double-luffed sails are prohibited. Loose-footed sails are permitted.
g. The sail shall have a maximum of six battens. Each batten pocket shall not exceed 60mm in width.
h. All measurements are to be taken to the outside of any bolt ropes (or their extension if necessary).
i. Hollows in the leach shall be bridged by a straight line to take measurements from.
j. The leech of the sail shall not exceed 5766mm (from head point to clew).
k. Girth of the leach mid point to measure not more than 1660mm. Leach mid point is the line that intersects the leach obtained from folding the head point to the clew.
l. No part of the foot shall be a greater distance than 5766mm from the head point.
m. The head of the sail shall not project out on an angle greater than 90 deg above the luff (using a set square with a 400mm straight edge along the luff, per diagram).
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mvr
Regards,
maarten van rossum
architect ANZIA ingenieur
mobile 021 2800 301
John Clinton
All,
There will always be ways you can improve a boat, and sometimes you should do that to keep it modern if there isn’t a major cost.
However, in this case I don’t see a real gain, but potential to change the class irrecoverably.
We changed to the sail profile a number of years back to modernise it at that time. In doing so we carefully changed the girths to try and retain the same area.
This didn’t change the sailing weight for the class and was generally a success.
I believe you should stay away from any rule that allows sails that will visually appear different in profile. In other words keep tight control on the girths that restrict the profile of the sail.
People are scared away from a class when they can see something different but don’t understand why or whether they need to spend the money to copy it. As Mark says, you don’t want people feeling they need to have multiple sails to suit the conditions, or to be buying new sails each year to keep up with the latest trend.
If you want to increase the sailor weight, then increase the sail area. But make sure the rules keep good control on the finished profile.
A simple rule as Mark suggests below would work if it had a maximum head width and didn’t allow any hollow in the profile (except between battens)
Be careful what you wish for!
Good sailing!
John
John Clinton
MacKay Boats Ltd
From: 3-7c...@googlegroups.com [mailto:3-7c...@googlegroups.com] On Behalf Of Mark O'Brien
Sent: Tuesday, 6 March 2012 9:01 p.m.
To: 3-7c...@googlegroups.com
Subject: Re: [3-7Class] Sail Change
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Benny
It seems i have created some healthy and opinionated passionate
discussion. Great.
Perhaps i misunderstood the process and for this AGM it should be
discussed under general business with a potential for there to be
further action by postal ballot.
I do understand this is a big change and one that does need serious
thought and working through to come up with a solution that will work
moving forward. (sorry there John)
Firstly Gavin, you were saying i have made changes in the rules to the
rig? This was never my intention and i cant see where you are
referring to.
My intention is to open up the sail shape and become more aligned with
the modern skiffs. ( 12foot, 18foot, I14, Devoti D1, Moth... etc)
My only real thought in not having any girth measurements was to speed
up the measurement process, to me it seems like a long tedious process
to go through every nationals. maybe there should be a girth
measurement at say 50% and 75% up the rig? A sailmaker or other
knowledgeable person may be able to come up with a good measurement
process if we are to change.
Basically my intention was to have a sail that:
is not allowed above the bottom of the top band on the mast
not past the inner edge of the band on the boom.
Complies with a 50% and 75% to be discussed girth measurement
In fairness we can sit on our computers and speculate about what the
extra sail area will do for different abilities and weights in
different windstrengths so Andrew Clarke is building one that should
be available to anyone who wants to test it out at nationals (after a
days racing or whatever...)
From where i stand there are a couple of key points
Square tops look sexy.
More power = on the wire earlier = more fun
More appeal for new people in the class
Now this last one is a moot point, but you put a sexy square-top on a
cool single handed fast skiff and by doing so open up the weight range
by 10? kilos... That has to help.
As with Andrew Brown, i would be interested to see how cheaply and
effectively one could be retrofitted onto an existing main.
Someone said a finn...
We all sail 3.7s... We know how exciting and fun they can be. Are you
telling me that because I am on the upper limit of competitiveness
weight wise in a 3.7, I should sail a finn, a boat that is seriously
hard work to sail, has a minimum presence in NZ other than at Olympic
level, and because of that carries a price tag for a competitive boat
at around 4 times the value of my car?
This is a great class. One that as i near the end of my weekends being
filled with Squadron Youth Programme i want to become more involved in
Cheers
Benny
Jonathon McMullan
Mark has an interesting point. Assuming we do move to higher tension rigs, do we all need new boats or is the increase in tension alright for our current chain plates etc? People might be alright with new sails and rigs but new boats might be the straw that broke the donkeys back. Boats are significant investments as it is without moving to a development concept like the 12s.
I'm open to suggestions.
Jonathon
Sent from my Transformer Prime
Luke Heslewood
Keep this all coming, im still interested on what derek and andrew think
There is some good comments coming in.
I quiet like maartens comment about a gennaker/ screacher.
I reckon having a furling screacher would be fun, but am affraid that
it will make the boat too hard to handle, IF this would be a
possibility I dont think that a bigger main would be necessarily.
having it stay up while sailing upwind would be good, no halyards to
deal with[ cleaner cockpit]
although, I think this will over modernise the boat, and put people
off, These could be a optional extra ?
Just a thought,
There will be more from me to come when I get home.
Luke
Jonathon McMullan
All this discussion over how to get more power out of a rig is great and all but an important fact might be getting overlooked. The wind range of a sail might be reasonably large but it is still fixed so by increasing the sail area, you can increase the weight of the sailor. But this also increases the minimum weight required, end of story. If you start changing the rig to allow 80kg+ sailors to wire in 5 knots, then there is no way that people in the 50kg, or even 60kg range can be competitive in anything over 15knots. Even people in the 70kg range might start struggling. I'm already struggling with too much power in 20-25 knots like we have had at a number of the previous Nationals competitions.
The alternative is to go to a multiple sail quiver which increases the net investment in sails from $1500 ($1600 for my nice new Technora :-)) to $3000 or possibly $4500. I'm not against turning up to Nationals and being an 'also ran' but only if it is because my sailing was pathetic and not because I couldn't afford to have the latest and greatest gear and got left behind.
So I guess what I'm trying to say is that remember there are sailors in this class below 70kg (myself included) and you would be forcing us out of the class into something else (please not a Zephyr or a Laser).
JM
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Daryl
From the UK perspective. Increasing sail area would destroy the
opportunity to build a class over here in the UK. The reason we have
had so much interest in the 3.7 in the UK is due to the size of the
rig. There is nothing else that small adults, ladies, girls can sail
if they want a trapeze boat. By all means think about relaxing the way
the sail is measured to allow for a a larger bigger head, but an
increase in overall size IMO would be very detrimental. You will kill
it over here. You could kill it in NZ too. Too big for a 3.7? Get a
RS600, Contender, Musto Skiff. Or go running and get on a diet! If you
increase the sail area you shift the boat into a different market
segment which is highly competitive / saturated. Bad, bad idea.
Daryl
On Mar 6, 8:58 am, Jonathon McMullan <jonathonmcmul...@gmail.com>
wrote:
> do we all need new boats or is the increase in tension alright for our
> current chain plates etc? People might be alright with new sails and rigs
> but new boats might be the straw that broke the donkeys back. Boats are
> significant investments as it is without moving to a development concept
> like the 12s.
>
> I'm open to suggestions.
>
> Jonathon
>
> Sent from my Transformer Prime
> 121KViewDownload
Gavin
this the ideal boat for the Youth Olympics? Instead of changing to a
square top, carbon hull, prod, raising the weight range etc. The link
for the YO's basicly asked for a boat that was exciting to sail and
watch, while being able to be home built - which a carbon/glass boat isn't!
http://www.yachtsandyachting.com/news/161772/One-Person-Dinghy-Bids
Perhaps to do this we might need to tighten the rules on the mast?
Maybe organising a deal where c-tech supplies a one design mast for all
new boats/purchases similar to what Fosters did for the Starling.
Current masts get grandfathered of course! I think the rules for the
sail shape would be adequate the same way the Opti's get away with
multiple manufactuers.
The square top only makes our sails look out of date the same way carbon
makes our plywood hulls look the same. Or hydrofoils, trapeze racks,
prod+genny make our boats look out of date. If you want to modernise
our boat where do you stop? Like Daryl says, there are other classes
you can bring to NZ if that's what you want!
Gavin
Piers Hugh Smith
I think looking at it, I can't see it having a huge effect on
boatspeed in any more than say 17knts (Rough guess), it isn't a
substantial increase in area. I also don't see it having a substantial
affect on the weight range either, so killing the class in the UK is,
in my opinion anyway (there are many more experienced with this kind
of thing than me), a bit sensationalized. Really what I see it doing
is adding visual appeal (Square tops are sexy) and giving everyone a
bit more fun in less than 12knts.
The relaxation on measuring the head of the sail to allow for square
tops is a great thing IMO, and I don't really see how otherwise the
rule increases overall area past 9.2m. A 0.2 increase in sail area
will probably not increase the weight range in the slightest. The
advantage with a square top is that they effectively depower more
efficiently, with a better leach profile- (becoming more akin to the
trailing edge of a foil in their horizontal profile).
From where I stand I can see this-
Pros-
Nice looking square top
Trapezing in +8knts instead of 10knts+
Little bit of development bringing the class slightly more up to
date.
Cons-
Making the current style sails less popular (but that could lower
entry costs into the class?)
Those who don't have it lose out slightly in marginal conditions.
A good case study for this would be the 49er I imagine, they have had
a minor increase in area to go to square top, and it has resulted in
the boats being easier to handle at both extremes of the wind range,
and the weight range has stayed roughly the same. At club racing level
over here we have two 49ers, one new one old rig- and they have very
level racing, with no real advantage due to the rig. I really think it
is mostly down to the sailor.
I'm pro for it- mainly because it makes it slightly more efficient and
looks nicer- and it doesn't increase the weight range at all IMO.
Piers Hugh Smith
Piers Hugh Smith
there are different ways of doing it though...
mvr
Regards,
maarten