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Sail flattening

Postby Lea Foster on Fri Oct 28, 2005 9:47 pm

Hi all,
I have been looking at the picture gallery with respect to sail shape off the wind. I see some of the top sailors on reaches with the characteristic diagonal creases that come with a tight vang. Is it a good thing to set the sail shape for upwind according to the wind strength and to maintain that throughout the race or is it better to make adjustments according to the point of sail as is the case with other classes?
Lea
Lea Foster
 
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Sail flattening

Postby Alan Riley on Wed Nov 02, 2005 8:52 am

Hi Lea,
You are better off making adjustments according to the point of sail. An upwind sail shape is too flat for going downwind, with the possible exception of survival conditions!

In medium and windy conditions you need a tight vang when going downwind, otherwise the leech twists off too much. However, it's a balancing act - too much tension and the sail goes too flat, not enough and you get too much twist. I generally find that the vang need to be eased about 5 cm when coming around the windward mark. Make sure that you let your downhaul off 2-3 cm too, otherwise you are compression bending the mast and unnecessarily stretching the luff of your sail. Similarly, let the outhaul off 3-5 cm to give plenty of power down low.

Regards,

Alan
Sabre 1564.
Alan Riley
 

Sail adjustments

Postby Lea Foster on Fri Nov 04, 2005 9:13 pm

Hi Alan,
Thanks for that info! I was wondering how much constitutes and adjustment and you have answered that for me. You are heading down for the Nationals no doubt, good luck with that. I'll definitely be at the Cleveland Nationals next year.
Lea
Lea Foster
 
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Location: Northern Rivers,NSW

Top telltale

Postby Lea Foster on Mon Nov 14, 2005 9:06 pm

I'm wondering if you may have some advice on trimming to keep the top of the sail aerodynamic? The top telltale seems to indicate turbulence and keeps dropping off to leward. Sometimes I have them all flowing and sometimes I lose the top one.
Woohoo 1679
Lea Foster
 
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Location: Northern Rivers,NSW

Sail adjustments

Postby Alan Riley on Tue Nov 15, 2005 11:49 am

Hi Lea,
Are you talking about getting the top telltales to stream when going upwind? There are a couple of things to check. First, where is the top telltale in relation to the mast? If it is too close, it will always be in an area of turbulence caused by the mast and you will never get your telltales streaming happily. I have my top telltale 50% of the way back from the luff. Second, if the leeward telltale is not streaming, it is because the sail is trimmed too hard for the angle you are sailing at. Either (a) you are pointing too low (b) you are using too much mainsheet tension (c) you have too much vang tension or (d) any combination of the above! In general, the leeward telltale is by far the most important of the pair, so always aim to have it streaming, even if the windward one is dancing around a bit. Sometimes you can get the leeward one streaming but can't get the windward one streaming without stalling the leeward one in the process. This is usually because the sail is too full. If this is happening at the top of the sail and you can't fix it with your sail controls, you may need a stiffer top batten (but don't go overboard)!
Hope this helps!

Regards,

Alan
Alan Riley
 

Leech tails

Postby Lea Foster on Tue Nov 15, 2005 4:54 pm

Hi Alan,
Thanks for taking the time to reply. I should have said leech tails and I need help with both upwind and beam reach. I think it is a twist problem and I just can't seem to get it right. Does what you have said about the other telltails apply to the leech tails too?

We had a gathering of Sabres at Richmond River Club last weekend and I had a look at the top guy's sail and it appears to be a much flatter cut. Mine is quite full. I have a friend who has a lot of sailing experience generally and he suggests that when going upwind the sail shouldn't be sheeted to the midline. He reckons that it will probably only be sheeted to the lateral corner of the transom. What would be your suggestion there?
Thanks again!
Lea
Lea Foster
 
Posts: 26
Joined: Wed Aug 18, 2004 4:39 pm
Location: Northern Rivers,NSW

Leech ribbons

Postby Alan Riley on Tue Nov 15, 2005 10:02 pm

Hi Lea,
Leech ribbons/tails are different from other telltales. They will tell you if the wind is staying attached to the sail all the way from the luff to the leech. If your leech ribbons are not flowing, there are usually two causes:
1. you don't have enough twist in your sail - usually caused by over-sheeting or too much vang. If this is the case, you will usually find the top leeward telltale will be stalled as well.
2. My suspicion, however, is that you were sailing in light(ish) conditions last weekend, because my experience ist that leech ribbons are only ever a problem in light conditions - in medium and heavy conditions it is hard to make them stall! In light winds it is very common in dinghies for the leech ribbons to stall, while the windward and leeward telltales both flow happily. Dinghy sails like on a Sabre are generally too full for light winds and lack the controls (eg. a backstay, or spreaders set so that you can bend the mast using more rig tension) necessary to flatten them to make them the correct (flatter) shape for light winds. However, if you make the sails flatter for light conditions, they are too flat for medium and heavy air sailing! Personally, although I have leech ribbons on my sail, I never look at the silly things. So my advice would be that if you find they frustrate you all the time, take them off! Just use the normal telltales, but particularly note what the top telltale is doing, because if the top leeward telltale is stalled, you can be sure you are oversheeted and the leech is stalled too.

As far as sheeting angle goes, on single handed boats like Sabres, Lasers, Finns etc., the sail needs to be sheeted fairly well off center in all conditions. Have you noticed that all Laser sailors worth their salt have the traveller set as tight as possible to make the boom sheet out as wide as possible, no matter what the conditions are? Sabres are similar, but because the sail area is a bit smaller, I find you don't need to sheet out quite as wide as for a Laser. In general, for light to medium winds, the boom is usually just to windward of the inside of the leeward bouyancy tank. In heavier winds, you can't hold it in that far, so just use a lot of vang and pull the sheet in as much as you can handle while still keeping the boat flat.

Sounds like Richmond River has a good fleet of Sabres to race with. I've never been there, but river sailing experts will have an advantage if you come down to Hobart for the nationals this year!

Regards,

Alan
Alan Riley
 

Telltails

Postby Lea Foster on Wed Nov 16, 2005 8:44 pm

That is great info! I thankyou and I will be looking at all that next time I sail. I wish that the fleet at Richmond River was as good as that. We have a fleet of one - me! The other guys were here as part of a three round Series between Cleveland, Southport and Richmond River. I hope that the display of Sabres might interest some of our other members who are looking at purchasing boats of their own. They might consider Sabres and we can get a fleet going. We have a predominance of NS 14's. I crewed for two years in an NS but my old knees and ankles just can't handle being sat on for and hour and a half!
Lea
Lea Foster
 
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Sail Shape

Postby petro on Thu Nov 17, 2005 12:36 am

I'd like to join Lea in thanking Alan for his advice on sail shape and tell tales etc.

I sail at Maroochydore where there are only a couple of Sabres and we are both feeling our way trying to get that ideal shape etc. for different conditions. Unusually, this year we have had a run of light conditions, including a couple of drifters, which have really tested our patience and resolve.

Although we have the "Sabre Book" and regularly pore through the various articles, Alan's advice seems to make it a lot clearer.

My background was in Thorpes (an older Queensland development class) where sail shape was mainly controlled by bending a fairly soft mast. I have found the Sabre mast does not want to bend (!!!) so it is a whole different ball game.

I'm sure Alan's advice is appreciated by all Sabre sailors , but particularly by those of us like Lea sailing in very small fleets in mixed competition with other classes.

Petro

Low Impact 633
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Sabre Book

Postby Lea Foster on Thu Nov 17, 2005 10:29 am

Hi Petro,
In your reply you mentioned a Sabre Book. Is this available somewhere to buy? You say you are from Maroochydore and Bob Jackson (Sabre Sailor from Cleveland Qld) mentioned something about a regatta up your way sometime around Christmas. If so can you give me some details?
Thanks,
Lea (Woohoo 1679)
Lea Foster
 
Posts: 26
Joined: Wed Aug 18, 2004 4:39 pm
Location: Northern Rivers,NSW

Sabre Handbook

Postby petro on Fri Nov 18, 2005 12:21 am

Gidday Lea

My older Sabre that I acquired last year came with a collection of memorabilia collected during the last 25 odd years by previous owners who have mostly been quite "senior" sailors who have kept "Low Impact" in immaculate condition!!

One item was a 116 page Sail that Sabre Handbook edited by John Snellgrove and dated March 1997.

It is a collection of contributions on sailing in general, and Sabreing in particular - many drawn from articles in the Sabre Rattle during the 70's and 80's. Topics include History, Sail Control, Tuning, Racing and Maintenance. It has helped me come to grips with the boat, but on some occasions the advice does seem a bit contradictory.

We also had a copy in our Maroochy Sailing Club library - donated several years ago!

I am unsure if it is still available ( possibly from the Victorian Assoc) but some other readers may be able to enlighten us.

Regarding Regattas - Maroochy doesn't have any scheduled around Christmas! We had a major one in early October that clashed with the Qld States! I was to be the PRO but my offsiders decided on the Saturday that they could handle the duties and it was time I spent a bit of time in my Sabre, God bless them!!!

Our next major Regatta is our Head of the River weekend on 18/19 March, incorporating the Corsair River Titles on the 18th.

Maybe our tacks will cross on the water soon!!

Cheers

Petro

Low Impact 633
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Sail flattening

Postby Guest on Fri Nov 18, 2005 8:32 am

If the book is still available i would love to get a copy

Thanks
ronny_f
Crispy
1201
(SA)
Guest
 

Sabre Manual and Maroochy Regatta

Postby Lea Foster on Wed Nov 23, 2005 8:59 pm

Thanks for the response Petro! Like you said, if anyone from the Victorian Assoc. is watching they may be able to tell us if the Manual is still available. The Head Of The river sounds really interesting and I've put it my diary.
Lea
Lea Foster
 
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Location: Northern Rivers,NSW

Sabre Book

Postby Sabre on Thu Nov 24, 2005 5:26 pm

The so called Sabre book is not an official Sabre Association publication even though all the information is verbatim from the official "Rattle" newsletters from the 1970s and 80's. The author, John Snellgrove is a past Vic Measurer. The book was published about 1997.

John is no longer a member of the association but I believe he is still at the address we have on file.

Try contacting John on 03 5986 1017

Barry Eastgate
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Sabre Manual

Postby Lea Foster on Sat Nov 26, 2005 6:58 pm

Thanks Barry!
Lea
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