Knots in Webbing Part Two

Having learned the Overhand on a Bight, let's see how to use it to rig an anchor.

RIG3: 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.

Uses:

Especially useful when the anchor is further back from the edge, and the anchor needs to be extended. Uses less webbing than making a loop.

WEB3: OVERHAND ON A BIGHT BY RETHREAD

We can create an Overhand on a Bight 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.

Uses:

The re-thread 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, the free end is then tied into an Overhand on a Bight with a rappel ring inside.

RIGGING A TWO-BOLT ANCHOR

Perhaps the most common rigging problem in high-traffic canyons, the following is the "Standard Rigging" for a two-bolt anchor.

RIG4: EQUALIZED, TIED OFF RIGGING FOR TWO BOLTS

This rigging, as shown, requires about 8 feet of webbing (2-1/2 meters).

[A]. Pass one end through one bolt hanger, through the ring, then through the other bolt hanger.

[B]. Pass the other end through the ring, and join with the first end using a Water Knot. Tighten.

[C]. Pull down on the Ring while feeding webbing through the bolt hangers.

(In this example, I have placed the tail of the knot on the inside of one of the bolt hangers, where it will protect the primary webbing from cutting across the sharp edge of the bolt hanger).

[D]. Point the ring in the direction of the rappel. With careful pointing, the load on the anchor will be equalized between the two bolts, each having pretty close to half the weight.

[E]. Taking the four strands neatly, tie an Overhand in the doubled Bight. Tighten neatly.

This is the TIED OFF part. By Tying Off, we prevent EXTENSION should one of the anchors fail.

Uses:

A standard tie-off for two-bolt anchors.

Comments:

- When tied neatly, this form looks so "finished" that even the most diligent of beginners are likely to leave it alone.

- Webbing can cut on the sharp edges of bolt hangers. Be sure to inspect the webbing where it passes through the hangers. For high-traffic canyons, it is best to use a Rapide between the sharp bolt hanger and the webbing.

- Glue-in Bolt Hangers tend to have a rounded surface that is webbing-friendly.

RIG5: EQUALIZED, TIED OFF RIGGING FOR TWO BOLTS, USING LESS WEBBING.

The standard rigging above is good, but it does require quite a bit of webbing. Here is a method to achieve much the same result, but using only 5 feet of webbing (1-1/2 meters).

[A]. Tie one end of the webbing to one bolt hanger, using an Overhand on a Bight via Rethread.

[B]. Thread the ring on the "other" end, and tie the "other" end to the other bolt hanger, using an Overhand on a Bight via Rethread.

[C]. Point the bottom and ring in the direction of the rappel, and tie off with an Overhand on a Bight.

Uses:

Similar to the Standard Two-Bolt Tie-Off, but uses less webbing - OR, extends the rappel point further using the same webbing.