UKC

Hi, I'm just learning how to lower off a sport climb and understand all the concepts. watched the bmc video and looked at the ukc article. Also seen someone else do it. Was just wondering however if I'm using a cow's-tail with a screw gate to secure myself (along with another quickdraw) was just wondering what the best lenght sling to have is? I need to buy some new kit and was wondering what would be the safest and easiest. Thanks, Derms

In reply to derms:

Its a tricky question - the answer for attaching yourself is that there mustn't be slack in the system once attached and therefore it depends on the exact position of the lower off relative to the footholds. That said, a 60cm sling is probably your best compromise.

In reply to derms: If you find out let me know, because whatever I do always seems to work out wrong!

In reply to derms:

I don't use a sling - make a cows tail out of a length of 7mm dynamic rope. Tie one end directly into your harness (just like your climbing rope) and have a fig 8 on the other end.
If it's about 50/60cm long it will clip to the back of your harness and not interfere with your quickdraws on your gear loop while you are climbing.

E

In reply to GrahamD: Thanks, a 60cm is probably what Im looking for then.

In reply to derms:

If you want something that's both safe and adjustable, then look at the Metolius PAS (personal anchor system) or the Grivel daisy chain - both of which have full strength individual sewn loops, unlike conventional daisy chains.

The downside is that they cost quite a bit more than a standard sling.

In reply to Charlie_Zero:
But they are awesome and save all that faffing about trying to get yourself to the right height for where you've knotted your sling

In reply to valentinesbabe:
I have one 120cm so I can clip the first anchor at arm's length when I'm tired and they've put the anchor too high and my pants are getting wet. Then a 60 cm for the other bolt, that I can sit on to thread.

I know that means there's a bit more shock if a bolt failed but it probably never will and if it did the extra shock probably wouldn't blow the other bolt...

In reply to valentinesbabe: Im probably no where near as experianced as you so dont mean to question, but I remember being told to never knot my slings. Any ideas why?

In reply to derms:

Best solution is to have one of the pieces of gear I mentioned above that are designed to be adjustable.

If using conventional fixed length slings, then sometimes the height of the footholds at the lower-off or belay mean that you will need a shorter sling than you have, so you can tie an overhand knot to shorten it. A knot will reduce the breaking strength of the sling somewhat, but the sling will still be plenty strong enough to attach you safely to the lower-off.

Shortening a sling with a knot is safer than using a sling that is too long (has slack in it). If you fall on a slack sling which is directly attaching you to an anchor, then the forces involved may actually break the sling as slings have very little stretch in them.

In reply to derms: When you knot slings they lose half their strength. So long as there is no slack in the system then what you are using it for will be fine (I think they are still rated about 10kn ...ish). The important thing about slings is to make sure their is no slack in them as they have no stretch and could easily break if shock loaded.

In reply to derms:
I f you pt a knot in a dyneema sling and then weight it, it is very difficult to untie.

In reply to Charlie_Zero: Thanks guys, you've cleared up alot up for me

In reply to Charlie_Zero:

DMM's testing showed that a slack sling with a knot in it breaks at a lower force in a fall than an unknotted slack sling, so the knot needs to be positioned so that the sling has no slack.

The advantage of using one of the lowering off methods shown in the BMC video is that you stay properly attached to the climbing rope at all times, so there is a backup for whatever you are attaching to the lower off with.

In reply to derms: The more important thing about knotting dyneama is that if you knot it, then shockload the sling, it's likely to break e.g the knot weakens it, unlike nylon slings. Obviously, if you load thing sling, but not in a dynamic way, it wont break if it's knotted, only if it's shockload, eg if you put one over a spike, knot it and then fall on it-it could break.

If you do know a sling then weight it, just tie in with a figure of 9 (bunny ears knot), then it's much easier to untie.

C

In reply to CragRat_Trad: *knot* and *tie it with a figure of 9*

In reply to Charlie_Zero: Could be wrong here. But doesn't a cow's tail reduce the strength of the sling already, which means that the knot would make no real difference?

That Metolius PAS does look like a nice idea if you sport climb alot though.

In reply to derms:

Might be too much info here if you are fairly new to climbing, but DMM's tests and the accompanying video have been responsible for an increased awareness of the risks of slack slings.

http://dmmclimbing.com/knowledge/how-to-break-nylon-dyneema-slings/

In reply to Dan1984:

I suppose it depends on the relative weakness of the lark's foot on the harness compared to the overhand knot. If the overhand was weaker then adding it would make a difference. I don't know the figures. Anyone?

In reply to derms:

You do know that most of the world just clips into a draw or two if they want it longer?