Knots are pure magic. I mean, you take this length of cord, twirl it into an esoteric shape and amazing things happen. A knot will keep you in place, let you descend slowly, and even untie itself only when needed. Magic, pure and simple. Sometimes, though, that magic can bite. Let's take a simple situation which we've all encountered, namely, joining two runners. Everybody uses a girth hitch, right? Well, maybe you should reconsider that. The girth hitch can reduce the strength of your runner combination to 66% of the strength of a runner/biner/runner combination. Toss in a spectra/nylon runner combination and you're potentially working with a setup that will fail at 10kN or less. Use THAT in an anchor and it could fail with the 6kN shock force generated by a leader fall onto a soft catch rope. *SNAP*. For all their versatility and magic, knots do something bad--they bend the rope. If you doubt this is bad, take a moment to think of a knife as a device that causes an unusually SHARP bend. The sharper the bend, the weaker the rope. So any knot will weaken that lifeline of yours. PANIC? ... well, maybe not. As a standard test of runner strength, climbing gear manufacturers will pull-test runners using 10mm steel pins at either end to simulate the force applied by carabiners in a climbing situation.

So one obvious solution is to slap a biner between the two runners, making sure that it can't get cross-loaded (separate problem, you figure it out). But if you don't have that biner, you will have to use...a knot. This is where the fun begins. What knot will join two runners, compromise their strength as little as possible, AND be easy to untie? A puzzle, a veritable mystery...and on it goes. Here's the tale of my adventures in KnotLand as hosted by the Knot Master himself, Mr. Chris Harmston of Black Diamond, to whom I owe a tremendous debt of gratitude for putting up with my curiousity. Once upon a time, long, long ago, there was a knot called... I. The Girth Hitch (spectra/spectra) II. The Girth Hitch (spectra/nylon) III. The Linked Girth Hitch IV. Black Diamond Girth Hitch Data V. The Climer Sling Hitch Confused? Well, you should probably use biners to link slings in a high load situation. Otherwise, a girth hitch should be just fine if the girthed runners are strong enough. Consider that 66% of 27kN is 17.8kN. An anchor that breaks at 17.8kN will support slingshot loads of 10.7kN. Check your rope and you'll find that it probably limits shock load to 10kN or less. The End --Karl