As soon as the geometry and the basic profile are established, a model of the sail is set into the rig plan. State-of-the-art software is able to accurately place this raw model into the rig geometry. This immediately gives the designer a sail shape, whose characteristics can be adapted based on the customer’s wishes and requirements. This step requires an extreme amount of experience and this is why the designers at Elvstrøm Sails spend many hours at the water. This is the only way that the shapes can be constantly improved!
The yarn guides are placed into these computer moulds. The trick here is to use as little material as possible and just as much as is needed. Only the best layout will give you the best weight to stability ratio and thus the fastest sail.
The density of the yarns used is measured in dpi (dpi = denier per inch) and indicates the number of individual fibres in the yarn per inch. This value is measured at a very specific point at the stern.
The illustration to the right shows the strings that bear the main loads on the sail (red); on the right you can see all the yarn guides of a high density EPEX sail. The so-called transversal strings are grey. Clearly visible is the particularly high yarn density in the sail corners. In some cases in a super yacht sail, the thickness of the material on the sail tack may be almost 2 cm.