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I agree it would be great to know the sailing weight of successful skippers. The problem is that is not a required measurement.
The lighter the skipper the faster the boat, every thing else being equal. From what I have seen a 55-57kg skipper can hold a Sabre upright to 20knots and few races are conducted above that. Yesterday my wife at 54kg, and slightly more in years, handled 30 knot gusts without problems going to windward bladed out at maximum hull speed, admittedly in flat water. For the technically minded; sailing 5% lower, only loses you about 25 seconds on an average length beat and after rounding the top mark the lightweight skippers disappear in the distance! Sailing lower the lightweight is the first to a new shift, which makes it even more frustrating for us heavyweights who fought to gain height on every gust.
In comparison, the Laser Radial requires slightly more weight,and its ideal is 55-65kg, although top skippers average around 63kg in sailing clothes as most major events are held in open water. It is interesting that coaches are now quoting 53-58kg as the target for women interested in training seriously for the Olympics. With its rounder cross section shape it carries weight better than the Sabre.
Another consideration is height. The Sabre design is optimal for a maximum height of some 170cm, which gives 61-65 kg weight for men and 59-63 kg for women.
Thus, I suggest the ideal weight would be 52-62kg. Certainly if you are above 70kg you need excellent strategic and tactical skills to be competitive.
However what really matters is to enjoy sailing your Sabre whatever your weight.
While the VYA yardstick is 126.5, the South Australian yardstick was 140 with the Laser Radial equal in both.
Having kept statistics from several championships with top skippers sailing I estimate the most appropriate yardstick would be 132-133. Over the whole wind range from 3 knots to 25 knots the Sabre only sails to its yardstick above 15 knots. The evidence is that in the low windspeeds the Sabre sails 7-8% slower than its yardstick when compared with other single handers such as the Laser Radial and Spiral.
ROD
The VYA has receivede little support in trying to keep the yardsticks up to date. I am just about to send them some relevant data based on results from the ACT dinghy championship. Most of my sailing activities these days seems to be in race management and I was RO for this event which attracted 77 entries. Conditions over 6 races varied from 3-20 knots.
The Sabre was well represented with top skippers including John Atkins, Natalie Farrel and Shane Navin. I kept leg and lap times for leading boats.
There was a very interesting result, Sabres had the widest spread of performance. In light winds, up to 5 knots, they sailed 7% below their yardstick, 5% below up to 12 knots. They could only keep to their yardstick above 15 knots particularily in heavy chop and going to windward. If you took other single handers such as the Spiral and Laser Radial then overall the Sabre sailed 6.2% below their YV yardstick. Cross checking with NS14s and Tasars confirmed the Sabre’s variation in performance.
My conclusion is that while the Sabre yardstick might be appropriate for the high wind conditions of Port Phillip Bay, they do not trully represent Sabre performance for most club conditions. Until recently the only other twoi yardsticks available were the South Australian at 140 and the LBG yardstick from the ACT at 133. Based on the data available around 134 would appear to be the true Sabre performance.
The reason this came up originally in the Sabre v Pacer context was looking at Club results were a mid national fleet Sabre skipper was being beaten by some of the eight club owned Pacers sailed by trainees with only 24 hours experience before going on to a racing skills course.
regards Paul
The point of the original question was to establish what is an appropriate yardstick for a Sabre to fairly compete in an open event. The YV yardstick is widely used but is not necessarily correct, one problem is few people bother to provide input. The reason I aked about Pacers was my experience in competing against several and finding it difficult to keep up.
The fact that a two sail boat points higher is not the question, which is how do they compare when sailed round a course in typical conditions. ‘Typical conditions’ is the problem. For example comparing the Sabre with a Spiral, a similar dinghy which is marginally quicker on the YV yardstick, the Spiral is 7% quicker under 4 knots, reducing to 4% quicker at 12 knots, but above 18 knots the Sabre comes into its own and is 2% quicker. If your sailing conditions are typically 8 knots compared with 15 knots on Port Phillip Bay, what is the appropriate yardstick?
My experience is that the Sabre YV rating is too high for yardstick racing at most clubs, and the YSA rating is more accurate. If the YV yardstick is used it reflects badly on the ability of a Sabre skipper.
Adjustable hiking straps are legal.
The system I use is webbing from front tank to about half metre from transom. I then use 3mm rope, some three turns to get the amount of slack needed to get the right length. My wife who is much shorter lets the adjustment out to get her best hiking position. The slack is taken up by shock cord fixed to the thwart so you do not miss the straps when going about.
QUOTE “No variations outside the Building Notes and Measurement Rules are permitted unless approved in writing by the Sabre Sailing Association of Australia Inc “
The problem is the Building Notes are only available if you are building a new boat. The present system is not satisfactory when only part of the measurement rules are openly available. The Building Notes should be precisely that, with a set of measurement rules which are published and stand alone. I know of no other class which does not make a full set of rules freely available to its members. The only rigging guide I have is of the Fico parts published in the early years of the class. the company is long out of business so why is it illegal to use modern fittings which serve the same purpose and give no performance advantage.
A typical problem I faced was I bought a new mast and was advised the construction notes required a bolt rope cut out. Now I am advised ‘rules’ have been changed to allow the track to be opened out to avoid weakness. I have just ruined a $300 mast because of measurement secrecy when all I was trying to do was have a legal boat. The mast is now weakened and the tack catches in the cut out.
What is the reason for requiring sails/foils to be remeasured every year? It is normal practice for other classes to measure only once. Does the Sabre Association expect its members to illegally alter them after they have been measured? Annual measurement might be a social occasion for metropolitan members but for country members it is expensive and time consuming. This is why very few bother to have an up to date measurement certificate. It is not true you can not enter a YA event without one, its just a requirement impossed by some state associations for competing in state championships.
The problem is the great majority of people rebuilding an old boat do not have a ccopy of the construction notes. An example is a simple replacement of a boom, I built one in accordance with the published measurement rules but now have been told it is illegal because the mainsheet block hangers are incorrect and not in the appropriate place. I find the whole processs rather frustrating when I am trying to comply with a secret set of rules which can not be published for fear of breaking copyright. Do I have to buy a set of consruction notes just to replace components?
What is the two shackle outhaul system?
I was building a boom last year and was told by the local shop that the towel rail was a Fico fitting no longer in production, so I just made up my own equivalent- a wire stretched between two L pieces being left over diamond adjusters. I saw the same on several old Sabres but have no idea if it is legal because there are no published Sabre rules. Just a set of measurements which in this case are irrelevant.
My Sabre came complete with a 30 year old copy of the Fico rigging guide, but as Fico went out of business no one seems to know what are legal commercial replacements.
The measurement limits 2638-2794mm are front of mast at deck level to rear face of transom. I measured a few boats at an open meeting and the average was 2665mm which became my starting point.
When starting to rebuild 266, the ballpark figure I was given for rake was 5620mm from bottom of black band to top of transom. This was a good starting point, but then it was adjusted after the first sail to get the boat balanced. Just begin with plenty of adjustment available on the side stays until you get the right length for helm balance.
The optimum rake will not only vary with the mast step position, but also with the sail shape, and fore and aft trim. Being fairly heavy I keep my weight well forward to minimize transom drag so use a little more rake than say someone of 65kg. My daughter at 58kg drops back two holes.
Perhaps there may be merit in having a copy of all the Sabre rules on the website, as at the moment the Rules and Measurement Section only details measurements.
I have found the measurement details are very useful since they went on the web site last July, with only a couple of minor interpretations needed since then to ensure the Sabre I am slowly rebuilding is totally legal.
Barry, I will measure the mast bend as you suggest as soon as it becomes warm enough to sail so I can datum mark the sheets and controls. One method I have seen of keeping the measurement line tight is to use light shock cord.
At least it will be easy on a Sabre. I have seen a trailable yacht prior to ordering an Irwin sail tape a ruler to a halyard and hoist it then use binoculars to sight the results!
Thanks for your help, all I need to do now is learn to sail.
Paul
Thanks Stephen for the response on mast cut out, the information was given to me by Bob, a real old time sailor/sailmaker from Adelaide.
My mast is ultra stiff but matches the original 1976 Ray Brown sail. I recently acquired a 1999 Hooper from Shane Nevin. As I said in a different topic. while attempting to flatten the sail by pressure my foredeck collapsed under the strain!
What I hoped to obtain in this topic was results from an objective method of measuring mast bend, for example by measuring the deflection caused by a specific weight suspended at the hounds. I thought of taking your advice on heating/slow cooling the mast to soften it but for some reason my wife vetoed the use of her hair dryer.
regards Paul
Thanks for your rapid and informative response.
As a result I spoke to Lindsay Irwin who advised that while he could cut a sail to any bend characteristic, a stiff mast is the quickest way to the back of the fleet. That might explain in part why I am there!
Lindsay put me in touch with Bob Keely who said most likely mine was an original Alcan mast which was far thicker, heavier and stiffer than modern masts. He also told me it was illegal anyway as the class rules required a cut out for the sail rather than the track being opened up. That interpretation must have got lost at the SA border.
regards
From what I have seen Hooper is predominate. Unfortunately there is no listing of what the top 10 SA sailors use such as the listing for Australiuan and Victorian champions contained in the Boats and Equipment section of this forum.
It is possible to build high performance foils which are light and stiff using fibreglass or exotic cloth.
There are two design approachs.
First, deriving the strength from the exterior using the core fundamently as a packing device. The core material can be foam, balsa or other light wood. Foils can be built by lay-up in a female mould or by shaping the core and male moulding. The latter is better for a one off production.
Second, deriving the strength primarily from the core and sheathing it with fibreglass. The core can be wood, laminated wood, or lightweight ply shaped to the final dimensions of the foil minus the thickness of the sheathing, say 1mm.
The choice of approaches depends on the thickness of the foil as the lightcore method derives its strength from the distance apart of the exterior materials.
The Sabre foils are very thin. The original concept was they were basically flat foils constructed from ply. The rudder is relatively moderately thick and not subject to excess sideways loading. It is therefore possible to build a balsa cored rudder. The centreboard is relatively thin, and subject to significant sideways force, and thus relies on the strength of the core. A balsa cored board would not be stiff enough without several layers of fibreglass making the total weight excessive. The optimal construction in terms of weight/stiffness ratio is therefore to build a wood laminate board and sheath. The result will be the lightest board for the required stiffness, it will be both lighter and stiffer than the traditional ply centreboard.
There has been substantial research on foil design but little work on the Sabre style parallel sided sections. However, research on Mirror foils some twenty years ago found NACA 4 digit shapes gave the best performance.
