Zag Wrench Tether

Many climbers have experimented with pairing the Petzl ZigZag and the Singing Tree ZK2 Rope Wrench for a smooth and compact SRT setup. (For some examples see https://www.tree-minded.com/2018/02/d...) Though a popular technique, this pairing is not endorsed by Petzl and it may void the ZigZag's 3-year warranty.

Most initial efforts to pair the ZigZag and Rope Wrench used double-legged stiff tethers made from accessory cordage. One problem with these tethers is that they are not completely stiff and they flex when ascending the line, which leads to tending issues. In some cases they also prevent immediate engagement of the Wrench, which puts extra strain on the ZigZag.

This tether is made of T6 6061 aluminum. A stainless steel D shackle connects the tether to the ZigZag and doubles as a tending point when climbing the line. The clevis pin, shackle, and cotter pin are attached to a 3/64" wire rope lanyard so that the individual pieces can not be lost when the Zag-Wrench Tether is disassembled.

A small Bump Stop made of a 3/16" diameter Chicago bolt is used to keep the Rope Wrench in the proper orientation. In the latest version of the tether, the Bump Stop can go in one of 7 holes arranged in a tight honeycomb pattern. Each hole lowers the angle of the Wrench 5 degrees to accommodate ropes from 11-13mm. A fine tuned Bump Stop placement is essential so that the Wrench engages immediately upon sit back regardless of the rope diameter or sheath texture.

Petzl prohibits use of the ZigZag on a single line without additional friction. The Rope Wrench provides additional friction and diverts 50% or more of the climbers weight from the ZZ links. If you climb this way it is important to inspect the ZigZag after each use for signs of wear since the Zag-Wrench Tether MAY subject the ZigZag to strain and wear that it was not designed for.