The following describes a retrievable rigging which utilizes webbing, a quick link or small carabiner, and a larger carabiner in a configuration much akin to the arborist's friction saver.
Like any other retrievable rigging which does not involve a pull chord, this rigging requires twice as much rope as the length of the drop. It is not releasable, in the sense that it is necessary to pull the end of the rappel side of the rope up through the rigging in order to retrieve it.
Its usefulness lies therein that all components are retrieved and nothing is left behind. As such, it conserves gear and lends itself to ghosting and building anchors using natural features. And unlike the CEM, it does not rely on any knots or hitches in a critical manner.
How to rig
Choose an anchor base – such as a log, tree trunk, or boulder – and take a piece of webbing about twice the circumference of that base. Use a water knot to securely tie the webbing into a loop and wrap that loop around the anchor base. Attach a quick link at one end of the loop and clip in a large carabiner at the other end. Feed half of the rope through both the quick link and the carabiner and tie a stopper knot at the end of the strand on the carabiner side. The stopper knot should be large enough to not pass through the quick link, and the carabiner should be large enough to allow the stopper knot to go through easily.
The rigging is now ready for double strand rappel. Should a single strand rappel be desired, add a carabiner block to the rope just outside of the quick link. (That is, at the very top of the strand without the stopper knot.) The strand with the stopper knot may now optionally be used for single strand rappel.
How to retrieve
The rigging is retrieved by pulling down the strand without the stopper knot. As the stopper knot travels back up to the rigging, it passes through the large carabiner, but catches the quick link and brings the webbing down along with it.
- A rookie mistake is to try to improve upon the above by tying the stopper knot between the quick link and the carabiner in order to retrieve the gear sooner. Doing so, however, would cause half of the rope to be pulled around and behind the base of the anchor and then back again, thus defeating the purpose of this rigging entirely. This is because the webbing is in fact retrieved from behind the base of the anchor and the rope has to follow the webbing, since it is threaded through the carabiner.
- Keep in mind that as the end of the rope comes down during retrieval, it will bring two metal pieces with it. The person retrieving the rope should be prepared for this and also make sure that there are no other canyoneers at the bottom of the drop.
- The anchor base should be chosen carefully as to allow for easy retrieval of the webbing. Should the webbing become hopelessly stuck, one may be left with no other choice but to cut and forfeit half of the rope.
- Related Bogley discussion