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Most sailboats are equipped with lazy jacks and lazy bags and most sailors would surely say this is worthwhile as not only they have never regretted the choice, but they couldn’t do without! A lazy jack is a network of lines and sheaves (or low friction rings) which is rigged to a point on the mast and to a series of points on either side of the boom. Their purpose is to hold the mainsail on top of the boom when it is lowered, thus avoiding to have it overturned on the deckhouse. Actually, it is not just a question of aesthetics or an attempt not to enter into port with your mainsail approximately tied in place, but above all of safety. Using a lazy jack reduces the crew needed to secure sails and ensures fast performance. In particular, during single-handed navigation, sail lowering operations are carried out by the sailor standing in the cockpit, unless unexpected problems arise.

A lazy bag may be provided together with a lazy jack. It is a kind of “bag” or better a cover that protects the mainsail but in first line it is meant to keep it properly on the boom. The cover is zipped and not only protects the mainsail from the weather and UV rays, but prevents the sail from possible flapping. It is customizable with the name of your boat. Although lazy jack and lazy bag complement each other, it is the lazy jack the best chosen by ship owners. The reasons for that may be many, and, last but not least the budget. However, the lazy jack is really cost-efficient if its huge benefits are taken into account. Kits ready to be installed are available on the market, such as Kit Lazy Jack PFEIFFER ( Those who prefer the do-it-yourself version can make their own lazy jack easily and cheaply. All what is needed are some metres of polyester rope and 6-8 very small sheaves or, as an alternative, low-friction rings.

If you are among those who choose to give up both sheaves and rings to make ropes slip through simple loops, be aware this may cause some rubbing or slowing down of the operations. And if you are a maker yourself, download drawings and/or tutorials on the web on the subject, or just take the boat moored next to yours as an example. The only difficult step is fastening to the mast the sheaves that will support the whole system and let it slide back towards the boom. If your boat is not equipped with a lazy bag, fasten the lazy jack to the eyelets under the boom. If on the contrary it is, fasten the lazy jack on the lazy bag which, as a result, will keep its correct shape. The ideal is, of course, to have both accessories as the mainsail cover ensures a higher distance on both sides of the boom. Consequently, hoisting and lowering are performed with a low risk of interference between the lazy jack and the mainsail battens. However, the system works also without a lazy bag, provided a little attention is paid especially in case of half-battened mainsails.

If a lazy jack is simple enough for anyone to make, this is not true for a lazy bag. This is a solid bag made of top quality materials such as Sunbrella fabric. It must be tailored to your boat, better if manufactured by an experienced craftsman. Its average cost for a small to medium boat is about 3-400 Euros, but you will be immediately aware that your money was well-spent. Finally, it is worth mentioning that  lazy jacks and lazy bags can be ordered from specialized companies by giving the exact mast and boom dimensions.

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