As climbers, we make critical usage of ropes and knots!
With so many niche knots and hitches and shanks, just what do you need to know? Here's a quick summary of a few that we reckon you should know, one you should be weary of and one we hope you never need but will appreciate knowing it, if you ever do ...
First comes up, the most critical interface, connecting you to the rope! It's the staple Figure of 8 knot, you should know this one inside out, you'll likely be tested on tying one when you register with a new lead climbing wall. Why's it so good? Various reasons. Firstly it's instantly recognisable whether it's tied correctly or not, there should be two neat parallel lines wrapping around a figure of eight shape, secondly it holds well when not loaded so isn't going to loosen off when you're halfway up a wall! On the flipside, this tightness is a bit of a downside - take a few falls when practising and you'll be struggling to untie it when pumped, hell I've honestly considered getting the emergency knife and just cutting the rope at times!
The nemesis of climbing wall Duty Managers the other option is the Bowline, deceptively simple, it is quick to tie and wonderfully easy to untie ... But here lies the problem, there have sadly been incidents where deaths (1) have been reported due to the failure of bowline when used to tie in and incidents of the knot coming untied, mid climb, eek! (2). Whilst a properly finished, with stopper knot, won't miraculously come undone, a relaxed tie-in might lead to complications. Not only that, it's much harder for your partner (Duty Manager) to glance at your knot and be sure it's correctly tied.
All-in-all, I'm a stickler, always using a Figure of 8, I'd rather my knot hard to undo than easier! ... That said, I'm hardly a Sports Climber so I have to acknowledge how much easier they are to untie there.
Now a knot that most Sport Climbers won't need but Trad/Alpine climbers will all be familiar with. Again there's a history of opinion about what knot is best for tying abseil ropes together, but finally consensus has been reached seemingly across the board, the knot to use is ...
"The Euro Death Knot"
Oh yes! This charmingly named knot is the one to use, quite simply and single overhand knot, neatly dressed and tugged tight. You can see why such an uninspiring knot got its nickname, it doesn't inspire confidence, but does everything that's needed of it. It stays tight when loaded, barely rolls, is small so is less likely to catch when pulling through and like the figure of 8, it's nice and easy to glance at and be happy it's tied correctly. The only precaution is to leave the tails long enough to accommodate for a bit of movement in the knot, but not so long that you attach your belay device to the tails not the main lines.
Keeping things concise, the next knot is the Double Fisherman's knot - perfect for tying two ropes of equal diameter BUT NOT FOR ABSEILING! This knot has one damn good use for in climbing though, tying Prussics - loops of 5-7mm cord that can be used to back up your belay device (/you) when abseiling, or in a worse case scenario, a pair can be used to climb a rope ... (But it's always best to have a micro-ascender or two on your harness instead as these are infinitely easier to ascend with!)
Anddddd finally, the knot I hope you never have to use in this situation is the Alpine Butterfly to isolate a damaged bit of rope. The example below isn't the best as you'd want a lot more rope coming out the knot where the damage is, but you can see how it works to isolate the core shot section. The only problem you now have is to pass a knot when ascending or descending the line, but that's a whole other kettle of fish!