Wednesday, 9 July 2014

Cruising Sails - Good versus bad, what difference does it make?

When talking to sailmakers about new sails, many people quickly get bogged down and preoccupied with the myriad of different fabric choices that are available and what can be large differences in price between one sailmaker and the next for what appears to be a similar product. Fabric choice is important of course as it will have a bearing on how well the sail lasts and how well it performs across time but it is really easy to over-look the rather fundamental issues of design and engineering when choosing your sails.

Of course fabric selection does make a difference, but it is the design itself, the actual aerofoil that the breeze gets deflected around that makes the biggest difference with regards to how the boat behaves and performs.

One question we often get asked is ‘all sailmakers these days design their sails on computers, so they should all be the same shape shouldn’t they?’

No! The computer is just a tool which the designer must be able to manipulate in order to produce the best shapes. Obviously the fabric choice is very important, but the advantages of having the best fabric are lost if the designer does not have the skill and experience to use the tools at his disposal. Similarly, the characteristics of a poor fabric cannot be covered up by clever computing. The advent of Computer Aided Design (CAD) and clever design programmes has meant that the difference between a bad sail and a good sail is not as obvious as it once was, but the differences are still there which is why it is even more important to err on the side of quality and reputation.

Believing that all sails are the same because all the sailmakers use computers to design them is akin to saying that all tailors use tailors dummies, so all suits are the same. As we all know, this is most definitely not the case!

The fact is there is no standardised aerodynamic shape for a given sail on a given boat. It is up to the sail designer to determine what the optimum shape might be and this will depend on the characteristics of the boat, the type of sailing it is likely to do (inshore or offshore, short handed or fully crewed etc), teh conditions it is likely to encounter and the level of experience of the owner. The sail designer will call upon his own experiences to determine what is best and the solution will clearly be slightly different from one designer to the next. 

The designer does not just concern himself with cloth selection and shape however. The designer is also responsible for the size, shape, and orientation of the reinforcing patches, the design of the batten pockets, positioning of hardware such as slides and cleats, making sure that as far as possible batten pockets aren't coincident with spreaders (including the reefed positions) and every other detail that you find on a sail. Typically, a more expensive sail will have had more time and effort afforded to it at the design stage, and will be more carefully engineered and manufactured to ensure the perfect fit first time, to ensure that the sail flies as intended and that it is as user friendly as possible.

So fabric choice, the skill of the designer, engineering and build quality are all contributing to the cost of the sail, but what will the differences actually be on the water?

The modern cruising sailor is increasingly aware of the benefits of having well engineered and constructed sails. Sails that hold their shape across a wider wind range allow for

·        Higher pointing: a well designed sail will point higher than a not so well designed sail. It will also be easier to trim

·        Less heeling: a boat that is heeling unnecessarily can be quite intimidating and uncomfortable for anybody, let alone the inexperienced or the family on a weekend passage. This will also affect the balance of the boat: less heeling means less weather helm.

·        Easier handling: a sail that holds its shape as the wind increases, or doesn’t go baggy when it is furled will ultimately be easier to handle. It is also likely to flog less which will contribute to the overall longevity of the sail.

·        The overall result is that the boat will get from A to B not only quicker but more easily.

Many cruising sailors may well feel that going faster is not important to them. This aside however, lets be really conservative and say that well designed sails will give you an extra 0.2 knots of boat speed for doing nothing else other than having them up and flying. An extra 0.2 knots equates to 400 yards an hour. On an 8 hour passage this is 3200 yards, or over 1.5 miles. How often would 1.5 miles translate into a missed tidal gate or missing a mooring for example? Being more realistic about the boat speed gain will result in the increased distance sailed or the time saved adding up considerably. It may also mean the difference between stemming a foul tide and having to kedge.

We have established then that the price differences between sailmakers can be attributed to quality of the fabric used, the skill and experience of the designer, and the quality of manufacture.

If you were buying a new washing machine you'd quickly establish that at one extreme you could buy one for maybe £150.00 but at the other extreme you might have to spend £1000.00 or more. Well they both just wash clothes don't they? At that point you'd start asking a few questions and you'd find out that the more expensive one has better quality components, it is better engineered, the manufacturer has a better track record, the after sales service is better, it is less likely to go wrong, it is more efficient (using less water and less electricity) and what do you know it actually makes a better job of its primary function, i.e. washing clothes (they come out cleaner and drier). If you still want to buy the cheap one at least you have made an informed decision.

When buying new sails you should have a similar set of considerations, price is important of course but it shouldn't be the primary driver in the decision making process and don’t be afraid to ask the sailmaker a few pertinent questions……

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