Top Tip #33 - Connecting Wires
Nuts, wires, Rocks, Wallnuts, Stoppers or Ultralights - they come with many different names and in a variety of shapes and sizes, but these simple metal wedges on a swaged wire loop are the staple of most climbing racks and they are a brilliant tool for so many protection requirements.
Infact, they only really have one significant problem. Sometimes, you place one in a crack and, because the crack lies a certain distance from an edge, when you come to attach a carabiner you can find that the biner sits over an edge (as shown in the photo below) in a position that could lever the carabiner across a weak axis - something to be avoided as carabiners are weak in this orientation.
It may be that you can change the location of the wire or it may be that this option isn’t available - if that’s the case you need a solution. Linking the wire via a sling looped through the wire loop with a lark's foot (explained here) or basket hitch (explained here) is an option but the abrasive wire could cut through the sling. DMM did some load testing on this (and compared it to the method detailed in this top tip) and the results are well worth watching in this You Tube clip here.
Another option is to link the piece using another wire - and that is where Peak Mountaineering Top Tip #33 kicks in. All you need to do is to take another wire from your rack, slide the nut down the wire (this can be tricky as some nuts are very tight on the wire) and then loop the wire through the other nut as seen in the photo at the top. You have now extended the wire far enough to make a new clip in point. Even better, the adjustable sliding nut from the new wire can even be positioned over the edge to offer some edge protection if needed. There are always compromises and this is no exception. The DMM video didn't highlight this as the strongest option but I still use it and the loading in the DMM testing was gradually applied rather than a shock load as might be experienced in a fall situation.
Manufacturers wouldn’t recommend using their products in this way and this is stated in the DMM video. This is simply sharing a solution to an advanced situation where it may be a good option and users need to make their own assessments of its suitability and safety - I am simply sharing the idea and take absolutely no responsibility for the safety of anyone that chooses to use it. It has certainly got me out of a tricky spot a number of times though.
Posted by Paul