UKC

In this vid,

youtube.com/watch?v=gRouOjS9avE&

he makes a W3P2 anchor (approx 8,000 lbs* in 1" tape), then goes and weakens it by tying a final overhand knot to 'equalise' it.

Since a W3P2 is self equalising, what is the final overhamd knot 'equalising', exactly?

(*It's a misconception that a W3P2 is good for "16,000 lbs".)

In reply to Jimmi:

Geez, I wouldn't want to be with him and trying to get off a mountain (with multiple abseils) in a hurry!

In reply to Jimmi:
Do you weigh remotely near 8000 pounds (whatever that is in a sensible measurement...)? Assuming not, it'll hold for an abseil. Fail to see the issue here.

In reply to Jimmi:

imho the final overhand knot just makes it easy to control clipping all 3 tape loops and it holds the tape knot snug against the tree.

Even with the overhand knot the setup is more than strong enough as an anchor

Davey

In reply to ianstevens:




It's about 35 kn I think.

In reply to Jimmi:

That fella is about as dynamic as the tape he's messing around with.

The overhand doesn't do much, but it doesn't weaken the sling to a remotely dangerous point.

In reply to Jimmi:

He is paranoid about backing everything up, like me

Water/tape knots are notorious for slipping, one of the reasons in the US they often used double fishermans for one inch tubular tape. Now most tapes are stitched.

The overhand means that if the water/tape knot goes pear shaped one wrap of tape is still integral/secure.

In reply to Jimmi:

A sling around the tree and linked to the rope with one locking crab does the job for me.

In reply to Jimmi:

You're right, it's not equalising. He ends up with

a) a friction wrap
b) backed up with a normally unloaded water knot
c) backed up with this overhand

So if the water knot "failed" and there happened to be magically no friction in the hitch you'd end up with a sling round a tree.

Using anything more than a basket hitch is probably overkill for most things.

In reply to Jimmi:

Never mind why the knot... why do these people MAKE videos like this? What purpose do they serve? Who is their audience?

In reply to Jimmi:

It's totally dumb. The W3P2 rigging is used in some rescue work where very high loads are anticipated. The entire point is mitigate the strength loss in the sling material that comes from the knot efficiency. Because of the friction of the two pulled loops around the tree, very little load is actually applied to the knot, so the weakening effect of the knot is diminished (and, with enough friction, totally eliminated).

By putting an overhand knot in the two pulled strands, this genius introduces a knot that will be fully loaded, thereby negating the only purpose of the W3P2 protocol, which he clearly doesn't understand.

For any ordinary climbing application, the strength loss in something like 1" webbing due to the knot is of no consequence, and so things like W3P2 are pointless. Moreover, if a W3P2 installation is left in place and reused by many parties, the potential to strangle the bark and kill the tree is greater than for a simple sling loop.

In reply to Jimmi:

Why not just tie rope round tree, I'd probably use a bowline, the rational would be I've reduced the complexity and the links

In reply to John Kelly:

One possible reason is that some trees have a lot of sap, and it can be really hard to get sap off your rope. Much better in that case to ruin some sling material.

In reply to rgold:

Ah, got it, Cumbrian hardwoods are generally better behaved than that but you make a good point

In reply to rgold:


But that doesn't explain why you would want to wrap the sling 3 times around the tree and throttle it when one loop will be more than sufficient and far less wasteful.

In reply to john arran:

As I said, the W3P2 method doesn't usually make sense for an ordinary climbing rap anchor.

But maybe I should qualify that a little. Since the method relieves the knot of most of the load, it would be good approach for a sling that is meant to be untied later (rather than left in place), because the knot won't be continually tightened by the rappel loads. If a few people rap on a sling joined with a water knot, it can be devilishly hard to undo that knot afterwards, and the W3P2 setup would make things much easier. Perhaps that is the context for the video I just heaped scorn on.

But there is still no good reason to put in that extra overhand...

In reply to Jimmi: Lived and climbed in USA for 7 years. My main question is : Why do Americans make everything so complicated?

In reply to jon: Other Americans?

In reply to johncook:


You mean like insisting on climbing with a single rope instead of running a pair of ropes all over the countryside?

In reply to climbwhenready:


Hahaha, you've taught me a new knot, slinging a sling around a tree!
You can't give that 'knot' a name!

In reply to rgold:

>By putting an overhand knot in the two pulled strands, this genius introduces a knot that will be fully loaded, thereby negating the only >purpose of the W3P2 protocol, which he clearly doesn't understand.

Bingo...

In reply to jon:

"Never mind why the knot... why do these people MAKE videos like this? What purpose do they serve? Who is their audience?"

Ostensibly, the reason is to 'help' others, but the majority are either company advertising or ostentatious ego displays.

In reply to Lusk:

That is the name though

In reply to Jimmi:

People make videos like this because they just like to look at the number of hits their video gets and think how important and useful they are in the world.

Most of these kind of videos are not only useless but badly put together. Try this one as an instructional 'how not too' How to sharpen a pencil:- youtube.com/watch?v=VkSmaFAuaH4&

In reply to Dave Perry:

Brilliant!

In reply to climbwhenready:

I always thought that the back of the knee didn't have a name

https://en.wikipedia.org/wiki/Popliteal_fossa

In reply to Dave Perry:


You'd have to try really hard to get a better one than this: youtube.com/watch?v=uWGcTvHtYQk& Just wonderful!

In reply to jon: Now I know how to do it. Shopping tomorrow for the gear (B & Q or Homebase?) and down to Millersdale for a try!

In reply to jon:

Or this seasonal instructional: youtube.com/watch?v=qMbF2kA5WAI& (Not Safe For Anywhere)

In reply to Jimmi:

This guy's my personal favourite :
youtube.com/watch?v=CbnCcpKoe1M&