Knots for Webbing and Anchors: The Overhand on a Bight
OVERHAND ON A BIGHT
The other "most-useful" knot in webbing is another overhand-type, the Overhand on a Bight. This is tied in webbing just as it is in rope.
[A]. Take a BIGHT and make a loop with it.
[B]. Insert the end of the bight into the loop, and [C]. Tighten.
Makes a strong end of webbing.
Can tie the bight with a ring in the bight, for the working end of a rap anchor.
Can thread the free end through the loop, making a CHOKE; possibly around a tree or rock. Having learned the Overhand on a Bight, let's see how to use it to rig an anchor...
RIGGING #1: CHOKE AROUND A TREE
[A]. Tie an Overhand on a Bight in one end of the webbing. Pass this around the tree and insert the free end of the webbing through the bight. This is a CHOKE.
[B]. Position where desired on the tree and pull tight.
[C]. Make a bight with the free end, with a ring inside the bight. Form an Overhand on a Bight.
This rigging is especially useful when the anchor is further back from the edge, and the anchor needs to be extended. It also uses less webbing than making a loop.
OVERHAND ON A BIGHT BY RETHREAD
Another way to make an Overhand on a Bight is by re-threading the knot, with the tree or rock inside the bight.
[A]. Some ways down the webbing, tie an overhand knot.
[B]. Pass the end of the webbing around the tree.
[C]. Retrace the knot with the end, making sure to leave enough tail. Tighten to set the knot.
The re-threaded Overhand on a Bight is useful for tying the end of the webbing to objects such as trees, rocks, bolt hangers and rappel rings.
In this example below, the free end is then tied into an Overhand on a Bight with a rappel ring inside.