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Why are there so many fabrics?!

» Posted on 12 Jul 2012

After a series of articles presenting the fabrics offered by the sail shop, I meet quite often with the opinion that back in the day sails were made using only one fabric, maybe just a few. And there were no such problems with the selection as today.

One of the examples that technology is not wasted efforts but is actually beneficial is an example of laminated fabrics made in a mould. It is an implementation of objectives ideal for the sailmaker. We have the ideal profile of the sail with perfect curvature, with the objective accurately transferred to the sail. The implementation of such a project is very expensive, but we can treat this case as a field for experiments, where the results are transferred to products for ordinary users. As we know, sails made using this technique are usually acquired for professional racing purposes. And such sails always cost a fortune. Whether today, or 100 years ago, in the era of cotton.

Looking through pictures from the first edition of “America’s Cup”, I am always in awe of how using material which is so little stable, so difficult to handle, such sails were made for huge and heavy boats. This is proof of the existence of something called the art of sailmaking (not to be confused with craft). It was assisted by knowledge, but above all by intuition. This is true today.

By returning to the heart of the matter.

Back in the day, there were limited materials available. Today, there are endless materials for every occasion and we only need to be able to take advantage of this.

For example, 100 years ago spinnakers were made of cotton. Unfortunately they were very heavy. Today, creating a spinnaker which weights “nothing” is not a problem for any sailmaker. I am attaching a photo of a spinnaker which I described about a year ago (on the boat “Skalar” during races in the late 1980s on the Gdańsk Bay).

 

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The spinnaker was made by Rysiek Bobrowski using plastic wrap. It weighed a fraction of what spinnakers made using normal spinnaker fabric weigh today.

Another sail on the photo – mainsail. Basic material was plastic wrap, which at that time we called the “Polish Mylar”. Although in reality this stuff never even lay next to regular Mylar. The fact is that it was made in Poland.

This material was made up of a layer of loosely woven polyester with a weight of about 80 g\sq.m. and a layer of polyester film weighing about 20 g\sq.m.

In regard to weight, everything was all right. In regard to quality, it was all wrong. But the sail made of this fabric was used normally for a full racing season under full load and without any slack (in 0-9 degrees Beaufort)

Why?

It was sewn in a radial cut – which as a rule is stronger than horizontal.

It has been reinforced in a “smart” way, i.e. where it was needed.

On the back edge, the gores consisted of three layers – Polish Dacron 165 g/sq. m. in the middle, Polish Mylar on the outside. In the middle part, the gores consisted of two layers of the Mylar, one layer was enough for the luff.

Regarding the racing value of this sail, I estimate it at 7-8 points on a 10-point scale. Point missing are for the stretchability of the entire system.

Both the mainsail and the spinnaker were made of materials not intended(!!!) for making sails.

The conclusion is that even with the worst of the fabric one can make a decent sail.

The sailmaker’s correct approach to the appropriate fabric must lead to a decent result in the form of an efficient and good sail.

All fabrics used for making sails today have such a safety margin regarding strength, that sails which get destroyed fast must have an explanation for this fact.

Most often it is their relentless treatment by their users. For comparison – a sail made for Mr. Smith for his private sailboat will be used for about 10 years (and longer). In contrast, the same sail made for the charter company can withstand 4 years, and that will be a good result. After these 4 years, it resembles a dish towel more than a sail.

There are also errors made by the sailmakers, such as too lightweight material, the lack of adequate reinforcements, lack of information about the need for putting UV fabric on the foresail, inappropriate hardware on the sails, etc.

The most common mistake made today by sailors regarding furled foresails is leaving the foresail on the stay for a longer period without a strip of fabric protecting against UV radiation.

I am presenting pictures showing the state of damage to the leech and the foot of the foresail as a result of the sun.

Edges of the sail were secured using self-adhesive Dacron, which was heavily burnt by the sun. Today, special fabrics which are 100% resistant to the sun are used for this.

The burnt self-adhesive Dacron looks weak but the structure of the fabric on the sail has not been compromised – and that was the main concern.

 

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Before the season, we get a lot of foresails with a dirty leech and foot for sewing on the UV fabric – “because it looks ugly.” Frequently these “ugly” parts are suitable only to be cut off, because they almost fall apart in hands. Such is the effect of the sun.

If someone does not like the strip of UV fabric on the sail, they can put on a cover when not sailing.

Anything, as long as somehow the sail is protected from the sun.

This is not fashion, glitz or anything such. This is an obvious necessity.

Currently, most foresails are the furled type, while 10 years ago furlers were in the minority.

And this is the reason for the lack of awareness of danger in case of some sailors.

Taking all this into consideration I can summarise the above text by saying that the basic version of a sail will meet the basic requirements – not all requirements related to their use. Only supplementing the basic version with the additions necessary for the given use profile will extend the life of the sail.