AN ANCHOR, A TOOL, A KNOT OR THE ART OF CAVING KNITTING
The technique being sometimes only an eternal restart, thanks to the appearance of new materials, we propose in this article an anchor, a tool and a knot so that the equipment of a cavity is carried out from sustainable and "innovative" way.
1- Anchoring: AF or drilled mooring Some call it lunule or even “abalakof”, but we prefer AF in reference to AN. The implementation of this anchoring consists in drilling in the rock a tunnel of small diameter (from 8 to 14 mm and preferably rectilinear) in order to thread an open ring of mooring there. Like all other types of anchors, its quality comes from the characteristics of its support and its installation, but it has many advantages: - Its longevity, thanks to the absence of mechanical stress from its vacuum support or from a chemical bond between the support and the mooring. - Its ecological impact, on a planetary scale, is reduced because it does not require any manufactured raw materials and almost zero "embodied energy". - Its financial cost, reduced to a perforator and a wick. - Its reversibility, thanks to easy makeup in case of uselessness. - Its discretion, for a pedagogical teaching of the techniques of always efficient equipment. Like all other types of anchoring, it also has its drawbacks: - Its discretion can make it invisible to some people. - Its use can be made difficult because of a strap or a cord that is too wide in relation to the diameter of the hole. - The mooring ring that passes inside can be "dropped". But if this ring shows signs of wear, then it will be easy to change it. - His subjective resistance. - Its implementation which requires the use of a perforator and the recovery of the important drilling powder.
This anchor is one more anchor in the panoply available to speleologists. There is no systematic in the techniques of equipping a cavity. Nevertheless, the field of application of this anchor is wide and its use should therefore satisfy the greatest number of people, except the visually impaired!
2- The tool: the hook The use of the AF requires the passage of an open mooring ring. This operation is sometimes made difficult due to an open ring that is too wide compared to the diameter of the AF. Or, the piercing configurations make it difficult to pass through. Also the use of a hook will facilitate this use. Manufacturing (10 minutes) 1- Dismantle a car windshield wiper. 2- Using flat pliers, bend one end to form a hook. 3- Using a steel file (or a Dremel micro motor), sharpen the hook so that it fits into the fibers of the cord or strap.
Using flat pliers, bend the other end to form a ring to pass a carabiner through. Implementation 1- Pass the hook through the AF you want to use. 2- Using the hook, grab the end of the cord or strap. 3- Remove the hook, and the open ring will follow.
3- The weaver's knot The use of this type of mooring makes it possible to connect directly to the progression rope without the intermediary of a carabiner. This has the advantage of relieving the speleologist without weakening the chain of resistance. Be careful however to comfort in the progression. Sometimes it makes more sense to have a comfortable, identifiable place to hang out. During the successive passage of speleologists, the closing knot of the mooring ring may become unreachable. And when removing equipment, you will have to use a knife or leave the ring in place. The weaver's knot offers several advantages: easy to adjust, allows a direct connection with the rope, is easily undone, was tested by the EFS during the test campaign on the use of the Dyneema cord in caving. Realization 1- Take the two ends of the ring and form a simple weaver in the loop of the knot. In the configuration of a single-point splitting, you may encounter some difficulties in going along. To avoid this situation, one can, for example, set up an ad hoc carabiner in the loop of the knot of the progression rope, or else make a diju knot (EFS notebook n°13: the dyneema cord in caving / p18).
In conclusion
The tests organized within the framework of the use of the dyneema cord in caving have shown that it is imperative to untie the rings after each use so that they can behave favorably in dynamics (under shock). This rule can therefore also be valid for ASs. In this untied configuration, the weaver's knot will give full satisfaction to AS users. Finally, the implementation of AF in the same way as the socket (Info EFS n°45/46) can be considered as an alternative to pins, but this is another subject that calls for another article.
Bibliography
ARNAUD Judicaël (2005)
La cordelette Dyneema en spéléologie (Les cahiers de
l’EFS n°13)
CAZES Gérard (2004)
Une alternative aux broches ? (Info EFS n°45/46)
MARBACH Georges / TOURTE Bernard (2000)
Techniques de la Spéléologie Alpine