The whole set-up was made of narrow webbing to reduce wind drag. We put the thinner webbing near the middle, and the widdest and most grippy on the slopes near the anchor and in the weblocks and linegrips. Alternating between different webbings has other advantages: it’s easy to tell, from the line or even from the ground, how far the highliner is along the line. They also have each their particular way of hurting your feet, which means you can endure more.
The weakest point of the set-up were the sewn loops of the SOS, which hold 24 kN, and the Pulsar back-up, which holds 26 kN. Indeed, in case of a back-up fall, a 3 meter extension doesn’t reduce the tension of a 2700 meter set-up by much.
There have been observations of burn marks on webbing, under the tapes used to keep the back-up in place. This happens especially after rain, and some lines have been fully destroyed.
Our theory is that while wet webbing conducts electricity, the dry part under the tapes acts as a resistor, and heats up. This can happen even when there is no lightning. We chose to not use any tapes, so that all the webbing would get equally wet
- Back-up and main were stitched, every 8 to 15 meters.
- Soft shackles were closed and locked with stitches or cord.
- Pieces of fabric were used at the connections to facilitate the sliding of the rings.
None of those “tapes” broke during the project.
We used pretty classic highline anchors, but made them stronger than you normally would as we were expecting up to 10 kN on the line. We used 6 bolts in some rock on one side, and 6 ground stakes on the other.
Together with some small A-frames, these were very comfortable anchors to manage the tension from, to tie in, and get off the line.