SURVIE – Cordages Noeuds

Comme DAB, le poids des mots mais le choc des fotos, ainsi donc pas plus d’explications inutiles
A AVOIR TOUJOURS A L’ESPRIT CELA PEUT DEPANNER

7 réflexions sur “SURVIE – Cordages Noeuds

  1. on June 20, 2012 in Skills


    McCarthy hitch

    To secure the tarp to an anchor point (e.g. stake or tree trunk) I prefer to use the McCarthy hitch, which is a simplified trucker’s hitch first showed to me by my friend Forrest McCarthy. If it has a real name, I don’t know what it is.

    1. Attach the guyline to a stake-out loop using a bowline; other fixed loop knots would work too (e.g. the Figure 8) but the bowline consumes less cord and it creates a nice round loop. Unless you replace the guyline cord in the future and/or reconfigure your system, you will need to do this only once.

    Cord attached to a tarp’s corner loop with a bowline.

    2. Run the guyline around the stake. The maximum distance between the shelter and the stake is a few inches less than half.

    3. Run the guyline tip back to and through the bowline loop, then reverse its direction 180 degrees again back in the direction of the stake, thereby creating a 2:1 pulley. Tighten the guyline until the tarp is positioned and/or tensioned correctly.

    Run the cord down to the stake, and then back towards the tarp and through the bowline loop.

    4. To secure the guyline, pinch the 2:1 pulley so that it can’t slip, then tie it off with a slippery half hitch.

    Tension the cord using the mechanical advantage, then tie if off with a slippery hitch.

    5. To undo the system in the morning, simply pull on the guyline tail in order to remove the slippery half hitch, then unthread the system. Don’t forget your stake!

    Tarp tied off to a nearby tree using the McCarthy hitch.

    Step-by-step directions: the trucker’s hitch

    The McCarthy hitch demands a lot of cord — about twice the distance between the tarp’s stake-out loop and the stake — so it is generally impractical for long guyline lengths, e.g. the ridgelines on an A-frame tarp. An alternative system is sometimes required too by the shorter guyline lengths, such as when a large rock is in the ideal stake position. In these instances, I use a trucker’s hitch with a slipped overhand loop.

    Watch a good YouTube video of this knot.

    1. Follow Step 1 from the McCarthy Hitch. Basically, tie the cord to the tarp with a bowline.

    2. Run the guyline to the stake, then tie a slip loop into the cord between the tarp and the stake. This slip loop will serve the same function as the bowline loop in the McCarthy hitch.

    Slip loop

    3. Run the guyline tip around the stake and up to the slip loop, then reverse its direction 180 degrees again back towards the stake, thereby creating a 2:1 pulley. Tighten the guyline until the tarp is positioned and/or tensioned correctly.

    Once you’ve installed the slip loop, run the cord around the anchor/stake and back to the slip loop. By threading the cord through the slip loop, you can create a 2:1 mechanical advantage.

    4. To secure the guyline, pinch the 2:1 pulley so that it can’t slip, then tie it off with a slipper half hitch.

    Tie off the trucker’s hitch with a slippery hitch so that it can be easily undone in the morning. I don’t tie off the knot more than this, but if you were really concerned you could add another slippery hitch.

    5. To undo the system in the morning, simply pull on the guyline tail in order to remove the slippery half hitch, then unthread the system. Don’t forget your stake!

  2. Butterfly Knot

    YOU'LL USE IT AGAIN AND AGAIN

    YOU’LL USE IT AGAIN AND AGAIN

    The following text is by Adolph E. Peschke as presented in the 1998 printing of the 1993 edition of the Pioneering Merit Badge Pamphlet:

    Great knot for tying a rope tackle!A butterfly knot is a fixed loop tied in the middle of a rope. There are a number of other knots that do the same thing, but the butterfly knot tends to work better because it doesn’t jam when strained and it’s easy to untie.

    Since it’s tied in a symmetrical fashion, strain can be put on it from any direction. Even though this knot is usually tied in the middle of the rope, you can also tie it at the end of the line if you need a fixed loop that is easily untied.

    The butterfly knot is a favored knot for mountain/rock climbers, used for hand or foot loops or used to hook their carabiners into. It has many uses in pioneering work.

    Pioneering Uses

    • When using a rope to pull a heavy object (such as a log), tie a series of butterfly knots to form loops for each person’s hand or shoulder.
    • When climbing a rope, you can tie a series of butterfly knots to form loops for your hands and feet.
    • To provide a fixed loop to use with a toggle.
    • When making a rope tackle, the loop in the butterfly not serves as the pulley. (See Rope Tackle.)
    • To tie up horses or anchor canoes on shore, tie a series of in a picket line for each horse or canoe.

    Great knot for tying a rope tackle!

  3. Rope Tackle

    Click on the image for a larger view.
    Simple 1-1 Anchor with rope tackle

    We apply a rope tackle where the guy lines meet the anchors for pretty much all our pioneering projects. For safety reasons, taut-line hitches should never be used in any pioneering work, because if the tension is eased the knot can slip.

    The rope tackle is one of the many skills learned for pioneering that can be used in a variety of situations for many years to come.

    Securing a load of spars to a flatbed for transport.

    Securing a load of spars to a flatbed for transport.

    Frequently, we use a rope tackle when creating a ridge line between two trees for dining flies and tarps, and love using them whenever there’s an appropriate need to hold the strain on a line being tightened.

    When you want to lift or pull more than your own strength will permit, or when you want to make a heavy lifting job a little easier, the rope tackle is a device that can be used.

    The idea behind a rope tackle is similar to that of a tackle using blocks and pulleys. In a rope tackle, one lead (end) of the rope has to be fixed. That is, it has to be anchored around a spar or tied through a ring or other piece of hardware that doesn’t move.

    Loop knot. Then a loop knot is tied along the standing part of the rope. The butterfly knot and the bowline on a bight are suitable for making a loop knot because they can be tied in the standing part of the rope and they are both easy to untie and fairly easy to untie even after being put under a strain. If you have no other reason to become proficient in tying these two knots, the rope tackle should convince you. Vertical display, as for lifting or pulling an object.

    Vertical display, as for lifting or pulling an object.

    Connect with the load. After you’ve tied the loop knot, it forms a fixed loop that acts as the wheel in a block. If you’re using the rope tackle to lift or pull an object, pass the running end through a ring or other hardware that’s attached to the object (load). The ring (or other hardware) is used so that the rope is free to slide as you pull on the hauling end of the rope as the tackle takes effect. If you want to use the rope tackle to tighten a line, pass the running end around a fixed object such as a spar, a stake, or a tree.

    Finally, the running end of the rope is passed through the fixed loop in the loop knot. The running end becomes the hauling line which is pulled to make the tackle work.

    Principles. The rope tackle works on the same principles as any other tackle using mechanical blocks or pulleys. The rigging method shown on the left develops twice the lifting or pulling power that’s applied to the hauling end. In other words, you can lift a fifty-pound weight using only twenty-five pounds of force on the hauling end.

    To determine how much force is needed to lift a weight, the general rule is that you count the number of ropes passing through the ring where the object (load) is. In this case there are two ropes passing through the ring that’s attached to the load. Then divide the number into the weight being lifted. Let’s assume that the weight being lifted is fifty pounds. The answer is twenty-five pounds, which is the amount of pull required to lift the fifty pounds with the rope tackle.

    When you take into consideration the friction of the ropes rubbing together, you will have to apply a bit more than the twenty-five pounds to make the lift. But even with the loss caused by friction, the rope tackle is quite effective.

    Sometimes it is better to actually experience the effect of how the rope tackle works than it is to understand the technical explanation of the process. Setting up a rope tackle will convince you.

    Tying off the Rope TackleTying off the Rope Tackle & Maintaining the Tension on the Line

    Tying off. When using a rope tackle, if you want to hold the position of a load being lifted or pulled, or if you want to hold the strain of a line being tightened, form a bight in the hauling end of the rope and tie it off with a tight half hitch below the fixed loop in the butterfly knot.

    Types of rope. The type of rope you choose for a rope tackle should have a low stretch factor, such as pure manila rope. Ropes that stretch like polypropylene and nylon, even though they are strong, require that you pull the stretch out of the rope before your tackle takes effect.

    Note: When in use, the rope tackle can put considerable strain on the fibers of the rope. Therefore, repeated use of the same section of the rope for this purpose should be avoided. The ropes used to make the tackle should be inspected for damaged fibers on a regular basis.

    Uses of the rope tackle. The wide range of uses for a rope tackle by a number of different craftsmen speaks for its effectiveness. Each craft seems to use a slightly different knot or hitch to form the loop that makes a rope tackle. The lorryman’s hitch, the lineman’s hitch, the stagehand’s hitch, are all samples of different knots or hitches used to form the loop. The only difference between these hitches is that in some of them the type of knot used to make the loop is more easily untied than others after a hard pull. But they all do essentially the same thing. That is, they form a fixed loop for the rope to be used as a tackle.

    The extent to which the rope tackle has been used by craftsmen and tradesmen in their daily work can be better understood from the following list of uses and by the various names by which it is called:

    • The linesman’s hitch is used to put strain on a line in the process of stringing electric or telephone lines. It was used as far back as the building of the telegraph lines that opened up the western states during the 1800s.
    • The stagehand’s hitch is used to adjust the height of the curtains on a theater stage.
    • The wagoneer’s hitch is an English reference to the hitch used to secure the load on a wagon or lorry.
    • The load binder is is what the farmer called the hitch he used to tie down a load of hay on his wagon.

    Pulling a log. One of the uses of a rope tackle is to pull a heavy load such as a log. To do this, you need two ropes. Tie a short (6′ to 8′) length of rope to the end of the log with a timber hitch. Then tie a bowline at the other end of this rope.

    Pulling a Log or Other Heavy Object

    Pulling a Log or Other Heavy Object

    To pull the log, tie a long line to a tree or other anchor point with a roundturn and two half hitches. Then tie a butterfly knot in the long line to form the loop for a rope tackle. Run the end of the long line through the bowline and back through the butterfly loop. Then pull on the end of the long line to pull the log.

    Pioneering Uses

    • To adjust the strain on the guy lines of a pioneering project or a flagpole (see figures 98 and 99)
    • To put the strain on a picket line used for tying up horses or canoes
    • To tie down and secure your equipment on a trailer or truck (see figure 100)
    • To hoist or lower equipment in rock climbing
    • To tie a line to air your sleeping bag or to make a clothesline for wet clothes
    • To tighten hold-down ropes on large tents and flies

    Uses for a Rope Tackle

    Uses for a Rope Tackle

  4. Timber Hitch

    TimberHitch

    Steps in Tying the Timber Hitch

     

    When putting crossed braces on a structure to keep it from racking (as used when making a trestle), the most important lashing is the diagonal lashing where the spars cross.

    TImber Hitch DrawingWhen the cross spars are properly assembled on the trestle, they will be standing apart where they cross. That is, there will be a few inches of space between the spars where they cross at the center of the X. To pull them tightly together, a timber hitch is used to start the lashing. As the timber hitch is pulled tight, the spars are sprung together.

    The timber hitch is a knot that can be tied quickly. As strain is put on the rope, the knot gets tighter, yet it remains easy to untie.

    To tie a timber hitch, first wrap the running end around the timber log or spar. Then loop the running end around the standing part of the rope, continuing to wrap the running end around itself a few more times. This will form a hitch that will tighten on the timber as the rope is pulled. After the timber is dragged or hoisted into position, the timber hitch is easy to untie.

  5. Rolling Hitch

    A Very Useful Hitch!John Thurman lists the rolling hitch as one of the essential pioneering knots. It’s similar to a clove hitch, but it’s a lot less likely to slip under a sideways pull. When securing a guy line to a horizontal spar, the rolling hitch can be used in lieu of a roundturn and two half hitches. It is also useful to attach a rope to another rope that has strain on it. Make sure that the direction of the pull exerted on the rolling hitch is against the double strand.

    As you become more involved in pioneering activities, you will find that there are many uses for the rolling hitch. After the roundturn is made, it supplies enough grip for you to complete the knot with ease, even when the line is under strain. Further adjustment can be made without completely untying the knot, by loosening the knot slightly, pulling the rope tight, and tightening the knot again.

    When the rolling hitch is tied to a spar, pull can be exerted either perpendicular to or along the length of the spar. After exerting heavy pressure, it will untie easily. When you need extra gripping power, just add extra turns. It works well with slippery or wet rope.

    Pioneering Uses

    When you want to tie a rope to a stake or a spar, the rolling hitch can be loosened easily to take up slack, and then retightened.

    To attach a light tackle, double the rope over to form a bight, and tie a rolling hitch with a loop for the tackle (see figure 11).

    To form a hand or shoulder loop to pull a spar, tie two rolling hitches, one at each end of a short rope (see figure 12).

    From Older Merit Badge Pamphlet

    The more you use it, THE MORE YOU'LL USE IT!

  6. Carrick Bend

    When you have to tie the ends of two large ropes (1/2″-diameter or larger) together, there is no better knot to use than the carrick bend. WHile many other knots reduce the strength of the rope considerably, a carrick bend reduces its strength only slightly.

    You’ll find that once a carrick bend is put under a big strain, it’s not all that hard to untie. The knot will tighten under the strain of the ropes, but won’t slip and works well with wet or slippery ropes.

    Tying a Carrick Bend

    The carrick bend looks very symmetrical when it’s first tied and is still loose, like two interlocking loops (see figure 18). But as soon as it’s pulled tight, it looks quite different and is often hard to identify.

    A carrick bend is used to thie the ends of two ropes together. Start by making an overhand loop at the end of one rope. To complete the knot, bring the end of the other rope under the overhand loop. Then complete the knot by weaving over and under as you go. When the knot is pulled tight, it looks very different.

    Pioneering Uses

    • To tie large diameter (1/2″-diameter or larger) ropes together, especially if there will be heavy strain on the rope.
    • To tie two ropes of any size together when the rope is wet or slippery and when you need a knot that will untie easily.

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