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The purpose of these articles is to inform cruisers of potential sail problems associated with bluewater cruising. Sail repair services in remote locations can be non-existent so sail reliability is key to a safe and stress free journey.  Luff Hardware - Standard Sliders Plastic slider or shackle failure is a common problem we see. In a heavy squall or while dropping the sail in heavy air, one slider failing can cause the rest to "pop" resulting in a flogging, out of control sail!  Mainsail with "popped" plastic shackles and sliders It is advisable to use the strongest plastic sliders available for each mast track. We use fiber reinforced plastic sliders or plastic coated metal sliders where possible. Un-coated metal sliders will almost never fail, but can cause wear on the mast track over thousands of miles. Sometimes there is no other option due to the type of mast track and size of sail. Attaching the sliders to the sail with plastic shackles can reduce some friction but isn't recommended as the shackles are prone to breaking with age, sun damage or excessive load. Attaching the sliders with webbing on to the luff is preferred. The trend with racing sails has been to machine sew the slider to the sail with webbing straps. Some sailmakers have carried this over to cruising sails. While this simplifies the manufacturing process, if a slider does fail it is not possible to replace the slider without a sewing machine, which of course involves removing the sail. The preferred method for blue water sails is to attach the slider to the sail with webbing though an eyelet on the sail or slot in the batten box. This is the strongest connection and if a slider does break it is possible to replace it yourself at sea with the hand sewing needle and thread found in the sail repair kit, or with a simple 2mm rope lashing.  Strong plastic coated S/S slider attached via webbing and eyelet and 2 ply patch Low Friction hardware Low friction hardware can be broken down into two categories, using the existing mast track or installing an extra external track attached to the existing track. 1. Existing track hardware Rutgerson wheeled low friction sliders - Either used only on full battens or on intermediate sliders. For certain mast types the wheeled sliders do a good job of reducing friction. Ronstan Ballslide system The Ballslide system does a good job of reducing friction via bearings running on the back surface of the mast. Once again, this system is only compatible with certain mast models. It is more expensive than the Rutgerson Sliders. For both systems we need highly accurate measurements to determine compatibility. Also of note is sometimes the presence of a close trysail track prevents these sliders being used.  Rutgerson wheeled slider 2. External track hardware Tides Marine Strong track A very popular cost effective solution for blue water cruisers. A low friction strong plastic track is slid up the existing sail track. This system is compatible with almost any existing mast track. The sliders are all S/S. The plastic track will last 10-15 years at which time it can be replaced, while the sliders can be reused. We have used this system on up to 60ft mono-hulls and 45ft Catamarans. Ronstan and Harken external bearing systems Ronstan and Harken both make external track systems that attach to the mast's existing sail track. They use cars with low friction torlon bearings and when sized correctly are very strong and low friction. Cost is quite high but for boats over a certain size this is the only solution. These systems work very well but do wear out eventually. Other types of external track. A few other types and brands of car systems do exist, for example the Antal, Facslide, etc. Each have advantages and disadvantages with a varied price. Normally a local rigger will advise his preferred system.  Tides marine strong track Sailcloth Part 2 - Dacron and woven HMWPE With so many different dacrons available it is hard for the sailmaker, let alone the customer, to figure out the good and the bad. Of course, if you read the marketing material every dacron is made to sound good. But the reality is quite different and only independent testing can shed some light on the true durability, UV resistance and quality of the fabric. Even between batches the quality can vary so most high quality sail producers test a sample from each roll to check it is up to standard; if not, it is returned to the cloth supplier. We have ongoing testing projects to find both the best dacron and the best value for money dacron.  Sailcloth samples ready for testing Stretch testing involves measuring the material stretch in three directions, the warp, the weft and the bias; in other words, up, down and diagonally. Dacron is the most stretchy diagonally due to only having fibers running in two directions. The diagonal stretch is controlled by the resin finish of the sail cloth. The harder the resin, the less diagonal stretch is present. Tightness of the weave also has an effect on diagonal stretch. However the disadvantage of a tight weave is that the yarns are smaller and so the cloth tears more easily. Smaller yarns are also more susceptible to UV damage than bigger yarns so the cloth will end up with a low tear strength a lot quicker than a material woven with bigger yarns. The firmness of the resin finish is a balancing act for cruising sails between performance and sail handling, especially for traditional slab reefing mainsails and hank on headsails. The harder the resin the harder the sail is to handle for the sailor. For this reason most cruising sails are made with dacron that has a medium finish - which still feels hard to most cruisers. Different resins break down at different rates so one of the ways we test dacron is to flutter the sample on a fluttering machine to see how quickly the resin deteriorates for each dacron sample.  UV testing involves leaving samples in the sun and weather for months at a time and then comparing the dacron to identical samples kept inside out of direct sunlight. The same machine used for stretch testing is also able to measure tear strength of sun damaged and undamaged samples.  Tear testing dacron sample Sailcloth - Woven HMWPE Our most popular high performance woven material is Hydra-Net Radial by Dimension Polyant. This fabric is a woven blend of polyester and super strong hmwpe (dyneema/spectra) fibers. The reason for its popularity is it offers a more performance orientated sail, but without the molding or lamination issues of a laminated material in high humidity climates. It also outlasts performance laminated materials by at least two times. However the price is higher, so the material is more popular on bigger or more performance orientated cruising yachts.  Hydra-Net radial mainsail
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