Rolling hitch

From ScoutWiki, For Everyone, Everywhere involved with Scouting and Guiding...
Revision as of 08:25, 18 January 2010 by Bot egel (talk | contribs) (Robot: Automated text replacement (-\[\[(ABOK)\]\] +\1); cosmetic changes)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search
Rolling hitch
RollingHitchNip.jpg
Names Rolling hitch, Magnus hitch
Category hitch
Related Taut-line hitch, Icicle hitch
Typical use Sailing
ABoK #503, #1190, #1465, #1681, #1734, #1735, #1736, #1791, #2555


The Rolling hitch (or Magnus hitch) is a knot used to attach a rope to a rod, pole, or other rope. A simple friction hitch, it is used for lengthwise pull along an object rather than at right angles. The Rolling hitch is designed to resist lengthwise movement for only a single direction of pull.[1]

A common usage while sailing is for rigging a stopper to relax the tension on a sheet so that a jammed winch or block can be cleared.

Naming

Names and reference numbers from ABOK, left to right: "Rolling Hitch(1)" (#1734), "Rolling Hitch(2)" (#1735), "Magnus Hitch" (#1736)

In the late 18th Century the knot now known as the Rolling hitch was called the Magnus or Magner's hitch, and the name Rolling Hitch referred to Two Round Turns and Two Half Hitches. In 1841 Richard Henry Dana, Jr. utilized the present-day names in his work The Seaman's Friend and subsequent authors have continued to use this terminology.[1][2]

There are two slightly different hitches commonly known by the name of "Rolling hitch". The Ashley Book of Knots identifies these two variations as "Rolling Hitch(1)" and "Rolling Hitch(2)" and numbers them #1734 and #1735, respectively. Despite the potential for confusion with the older usage, Ashley chose the name "Magnus Hitch" to refer to knot #1736, which is simply #1734 tied with the final hitch made in the opposite direction.[3] Since two distinct variations of the Rolling hitch are widely referred to by the same name, and Magnus hitch now may refer to a different knot than it used to, the use of Ashley reference numbers for these related hitches can eliminate ambiguity when required. These hitches are pictured at the right.

Although some sources fail to differentiate by using a separate name, when a Rolling hitch or Magnus hitch is tied around the standing part of the rope to form an adjustable loop it is often referred to as a Taut-line hitch or one of several other names.

Tying

Rolling Hitch(1) #1734

This version is preferred when attaching a rope to pole or rod.[3][4] It is effectively a clove hitch with an extra initial turn.

RollingHitch-ABOK-1734.jpg

  1. Start with a turn around the object. Bring the working end towards the direction of pull and between the standing part and the object.
  2. Make another wrap around the object, completing a round turn. The wraps of the round turn should progress towards the desired direction of pull. Bring the working end out over the standing part away from the direction of pull.
  3. Complete with a half hitch, moving around the object in the same direction as the first turns, as for a clove hitch.
  4. Dress by snugging the hitch around the object before applying load.

Rolling Hitch(2) #1735

This version is preferred when attaching rope to another rope.[3][4] The first two turns create an Awning hitch - a temporary hitch used by riggers when adjusting tent lines.[5]

RollingHitch-ABOK-1735.jpg

  1. Begin by making a turn around the object, bringing the working end back between the object and the standing part. Cross over the standing part away from the desired direction of pull.
  2. Make a second turn that exactly follows the first, and hence also passes between the object and standing part and then crosses over the standing part, away from the direction of pull. Make sure the second turn "tucks" between the first turn and the standing part; that is what gives this version extra grip when made around another rope.[6]
  3. Finish with a half hitch, moving around the object in the same direction as the first turns, as for a clove hitch.
  4. Dress by snugging the hitch around the object before applying load.

Magnus Hitch #1736

This is tied exactly as #1734, but with the final hitch in the opposite direction. It can be more tricky to snug-up, since both lines emerge from the same side of the hitch, but it has less tendency to twist under load.

MagnusHitch-ABOK-1736.jpg

  1. Start with a turn around the object. Bring the working end towards the direction of pull and between the standing part and the object.
  2. Make another wrap around the object, completing a round turn. The wraps of the round turn should progress towards the desired direction of pull. Bring the working end out over the standing part away from the direction of pull.
  3. Complete with a half hitch, moving around the object in the opposite direction as the first turns, as for a cow hitch.
  4. Dress by snugging the hitch around the object before applying load.

Security

The load should always be applied from the side with the two turns. Ensure the hitch is very snug before applying any strain, else it will not tighten further under load. When hitching to another rope, Ashley[3] and other sources[6][7] suggest #1735 is more secure. Ashley also states that #1736 has less tendency to twist.[5]

Though effective for moderate loads, the Rolling hitch cannot be depended on to hold fast under all conditions. Using stiff and slippery modern fiber ropes, the Rolling hitch may be difficult to make hold at all. Friction hitches with additional wraps and more complex structure, such as the Icicle hitch, may provide more security.

See also

References

  1. 1.0 1.1 Clifford W. Ashley, The Ashley Book of Knots (New York: Doubleday, 1944), 292.
  2. Richard Henry Dana, Jr., The Seaman's Friend: A Treatise on Practical Seamanship, 14th Edition (Boston: Thomas Groom & Co., 1879; Dover Republication 1997), 49.
  3. 3.0 3.1 3.2 3.3 Ashley, 298.
  4. 4.0 4.1 Nola Trower, Helmsman Guides: Knots and Ropework (Wiltshire: Helmsman Books, 1995), 31-32.
  5. 5.0 5.1 Ashley, 304.
  6. 6.0 6.1 Animated Knots by Grog. Rolling Hitch. http://www.animatedknots.com/rollinghitchboating/
  7. Brion Toss, Chapman's Nautical Guides: Knots (New York: Hearst Marine Books, 1990), 30-32.

External Links