Rigging Small Sailboats
Chapter 2
.....rigs and sails
Page 3ANATOMY OF SAILS
The common triangular sail is best discussed by referring to parts OF the sail, and parts IN the sail, or the actual components used in the construction of the sail. Our discussion of sail anatomy is comprehensive, but note that not all sails will have all the items mentioned. Fig. 2-6 should be followed in the discussion of sail parts. Now for the parts OF a sail.
The LUFF of the sail is the forward part, or the part which is considered to meet the wind first. The LEECH is the aftermost part, while the FOOT is the lower edge of the sail. The HEAD of the sail is the topmost corner; the TACK is the forwardmost corner, and the CLEW is the aft corner of the sail. The ROACH refers to the up and outward curve in the leech of the sail. The amount of roach will vary with the sail. The lateen-type sail has little or no roach, while mainsails used on catamaran sailboats have considerable roach. Next, we will describe the parts built IN a sail.
FIG. 2-5 -This GLEN-L BUCKBOARD uses a simple LATEEN RIG. The sail has a sewn-n sock along the luff at the clew to attach it to the tubular aluminum spars. No battens are used in the sail. This mast is also free-standing. |
To the beginner, the most obvious part built into the sail is the INSIGNIA and sometimes a group of numbers. The insignia usually tells graphically what the name of the boat class is, while the number refers to the registration number given to that particular boat in the class organization. Obviously, not all sailboats belong to a class, nor do they all have numbers on the sails.
Most mainsails have BATTENS built into them. These are semi-rigid thin strips, either of wood or synthetic material such as fiberglass or plastic, used to maintain the shape of the sail when underway. The battens fit into BATTEN POCKETS sewn into the sail. Battens in order to stay in the pocket can be tied in. A better type uses what is called a "lock-sleeve" pocket which makes it impossible for the batten to slip out, but can readily be removed so the sail can be folded. Battens are usually located at almost right angles to the leech, but sometimes one or two battens are located along the foot at right angles on LOOSE FOOTED mainsails and some jibs. A loose footed sail is one that is attached only at the tack and clew points along the foot. The boats in Figs. 2-2, 2-3, 2-4, and 2-5 all have loose footed mainsails. The position and size of the battens is usually determined by the sailmaker or the designer of the boat. Some sails, especially on certain catamarans, use battens which span clear across the sail.
FIG. 2-6 -The "anatomy" of a typical set of working sails. The two dimensional drawing does not truly show the actual three dimensional shape which the sailmaker sews into the sail. This "shape" allows the sail to form correctly to the wind, even though the sail appears to be a flat piece of cloth. |
Other parts built into the sail are primarily those used to attach the sail to the rigging. At the head, tack, and clew, most sails have CRINGLES built in for attaching the sails. These are merely grommets which reinforce the sail at the hole. Most mainsails have extra sail reinforcing at the head of the sail and this is called the HEADBOARD. The strains on the sail at this point are great, and the headboard with a cringle through it distributes the stresses.
Several methods are used to attach the sails to the mast, boom, or rigging. The jib and Genoa are attached to the forestay in sloop rigs with HANKS or snaps (Figs. 2-7 and 2-8). These are special hooks or rings used to secure the sails to the forestay as well as allowing them to slide up and down. The hanks are usually sewn into the luff of the sail. Probably the simplest method of attaching the mainsail on lateen rigs, or in boats which have free standing masts, is by means of a "sock" sewn right into the sail which slips onto the spars. Two varieties of sock-type sails are shown by Figs. 2-4 and 2-5. The sock-type sail is limited to very small boats, but makes a neat and inexpensive sail. Also used on small sails are loops or line which fasten around the spars.
FIG. 2-7 -Snap-type jib hanks sewn into the luff of the jib are used to attach the sail to the forestay. |
FIG. 2-8 -This type of jib hank takes just a twist of the wrist to secure it to the forestay. Larger jib sails usually do not use this type as they are not as strong as that shown in FIG. 2-7. |
On most boats, the mainsail is attached to the aft side of the mast in usually one of two ways. The first method is with TRACK SLIDES, pieces of hardware sewn to the luff of the sail at intervals of several inches, and which slide on a track fastened to the mast. A better and more common method is the use of a BOLT ROPE. This is a piece of rope the length of the luff and sewn right into it. The bolt rope fits into a groove built into the aft side of the mast. On sails which are not loose footed, this same bolt rope and groove can also be used for attaching the foot to the boom. Or, if track slides have been used on the luff, they too can be used on a track fixed to the boom. For details on spars (mast and boom), see the next chapter.
To be continued in the next WebLetter