There are many of equalising a sling while climbing, and this month’s tip will introduce two of the lesser known methods.
Equalising a sling with an overhand knot on a bight
One very commonly-used method involves an overhand knot on a bight. I’d go so far as to say this is probably the most popular method in the UK. It’s certainly the one that I probably use most of the time. It’s quick and easy to set up and I teach it often on climbing courses. But it does have a couple of drawbacks.
First, it uses a relatively large amount of sling material to tie. If the anchors are a little too far apart, then there may not be enough sling material available to tie the knot while still keeping an angle of less than 90 degrees at the apex of the sling. Secondly, once it is tied, it is quite difficult to make minor adjustments if you realise that you didn’t tie the knot in exactly the right spot.
The crucial thing to remember when using this method is to make sure that the knot has included the strand of tape running from anchor to anchor. You must grasp this section and pull it down to join to the rest of the sling. If you fail to do so, you will have created the “death triangle”. It’s easy to check though. With two anchors, there should be two strands of sling running into the knot on each side of the knot, and two loops of sling where the karabiner gets attached.
Equalising a sling with a sliding overhand knot
An alternative method of equalising a sling also uses an overhand knot but in a different way.
With this method, first you clip the sling into one anchor and then loosely tie a simple overhand knot in the sling at the point where you estimate the load will be. Then clip the other end of the sling into the second anchor. Next, gently pull the overhand knot towards where the load will be, adjusting it as required. Once the knot is in the correct spot, you have, in effect, two short slings of exactly the right lengths. You must clip the karabiner into both loops of sling that come from each anchor. Finally, once fully loaded, it should look like the karabiner is clipped into two mini-slings.
This method of equalising the sling removes both of the problems associated with the first method. It is easy to adjust accurately once the knot has been tied initially; and it uses next to no sling material. It doesn’t take long to set up, but as it is a little fiddly it might take slightly longer than an overhand on the bight.
Equalising a sling with a clove hitch
The second of the lesser known methods of equalising a sling involves a clove hitch.
Clip both ends of the sling into the two anchor points. As with the first method (overhand on the bight), make sure that you grasp the strand of sling running between the two anchors to include it in the clove hitch. As with that first method, bring the two strands of the sling down to the apex of the triangle where the load will be. Now, instead of tying an overhand on a bight at that point, simply tie a clove hitch and clip the karabiner in at that point.
Like the second method, this uses only a small amount of sling material and is still easy to adjust once tied. In fact, it’s probably the easiest of all three to adjust once tied.
- Overhand knot on a bight method – Quick and easy to get right once well-practised. But slow to adjust if you estimate it wrongly, and it uses a lot of sling.
- Sliding overhand knot method – Uses a minimal amount of sling and is easy to adjust accurately once tied. But it is a little fiddly so can be a bit slower to use.
- Clove hitch method – Uses only a small amount of sling material (somewhere between the other two methods). It needs care to get right first time if you are not well-versed in tying clove hitches. But, since it is a clove hitch, it is very quick to adjust accurately once tied.