The sheet bend is one of the useful knots for scouts, mountaineers and sailors to learn. It is the most important knot for joining two ropes of unequal thickness together strong and simple. A permanent loop tied, seized or spliced can be substituted for the right hand portion of the knot. Ropes with a difference of sizes will not slip when the sheet bend is properly tied.
Given Names | Becket bend, Weaver's knot, Weaver's hitch |
Scouting Class | Tenderfoot/Membership |
Typical Use | Joining two ropes of different diameters |
Condition | The knot may lose if the both bitter-ends of the lines are on the different sides of the knot. |
The sheet bend is related in structure to the bowline. It is very fast to tie, and along with the bowline and clove hitch is considered so essential it is knot No.1 in the ‘Ashley Book of Knots’. It is a more secure replacement for the reef knot (square knot), especially in its doubled variety.
It is important that the tag (free) ends of the sheet bend be on the same side of the finished knot. For more security use the doubled version which is the same as the single version but with an extra coil around the standing loop.
This knot is strongest when both bitter ends are on the same side. To increase the strength of the knot when using lines of different diameter you should tie a double sheet bend.
TYING
Each rope has a loop in it which binds the other rope. This knot is identical to the bowline except that in the bowline the other end is used to tie the knot.
The sheet bend may be tied by various methods: the basic "rabbit through the hole" method of forming a half hitch in the bight of the larger rope (similar to the method used by an experienced sailor or mountaineer to tie a bowline) or by a trick method, involving upsetting a noose knot over a short end of the "larger" rope. For maximum strength it is desirable to have the free ends on the same side of the knot.
A loop is first formed with the thicker rope, the thinner is then threaded through this loop, Fig. A, passed right around the end and standing part of the thicker rope B, tucked under as in C and tightened by pulling on the standing part of the thin rope, D. You can see how the thin rope jams against the loop of the thick rope to prevent it from slipping. If the ropes are of very unequal thickness, or placed under a lot of tension, it is recommended to use a Double Sheet bend.
Double sheet bend
When lines are of unequal diameter or rigidity it is necessary for security to "double" the sheet bend by making an additional round turn below the first and again bringing the working end back under itself. The free ends should end up on the same side of the knot for the maximum strength. In this form, this knot will even hold in slippery nylon rope. Not for use by climbers through.
USES
The Sheet Bend is recommended for joining two ropes of unequal size. The larger rope must be used for the simple bight as shown. It works equally well if the ropes are of the same size.
It would replace the Reef (Square) knot except for the awkward fact that it has to be tied with both ends loose in your hands with no load on the ropes (The reef - with all its faults - can be tied tight against a sail, or parcel, and usually stays tight while the second half hitch is tied).
Sheet bends are also used for netting.
HISTORY
The sheet bend has a long history and dates back to the days when sailing vessels lined the seas. Sailors named it in the days of sailing ships when they would "bend" (tie) the "sheets" (ropes attached to the clew of the sail) that attached to the sails.
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