UKC

Hi folks,

Hoping to gain your opinions on something I noted last weekend when taking a buddy who has never climbed before to an indoor wall.

I had taught him how to tie on with a re-threaded figure of eight knot (what I believe to be the standard knot used for this although I understand some people do use a bowline - that's for another discussion!).

I noted however that on his third or fourth time of tying on he had missed a step and had in fact tied a re-threaded overhand knot. I had been checking each and every time so this was the first time he had done this - he had tied on with perfect figure of eights previous to this.

My main question is in the top-roping scenario we were in, on easy routes, with a taut rope what are the potential issues (if any) with this?

I'm not asking because I expect to use this method - it's simply a hypothetical question out of interest.

I use the overhand on a bight and indeed the re-threaded overhand knot in rigging and in abseiling and we know it to be a strong knot.

The major issue I can see with it is the fact that with less rope involved it would tighten up more than a figure of eight but asides from this what other issues could there be?

Thanks in advance.

Jake

Main risk is not being able to open the knot once loaded. Fine from a safety POV.

CB

As mentioned, if you take a fall on one it'll be mentally hard to untie. Best pack your marlinspike once he starts leading.

Thank you both!

I thought that would be the only real concern - wanted to make sure I wasn't missing some obvious (or not so obvious) safety issue.

Thanks

It's plenty strong enough, as are many botched fig-8 rethreads which is I think one of the reasons the 8 is so popular. The overhand does pull very tight when loaded but in a toprope climbing situation you'd really struggle to pull it so tight it can't be undone without tools.

jk

I have a friend who's used it as his strandard tie-in knot for years. He never has any difficulty getting it undone, but then he also doesn't work routes on lead much - prefers to toprope or go carefully from bolt to bolt until he feels he has a decent redpoint chance, then go for it without falling.

The other issue with an overhand is that it'll likely send floor walkers at the wall into paroxysms ! but perfectly strong enough.

Yes I can imagine the anally retentive having much difficulty comprehending it.

But then perhaps I am one of them for questioning it?........oh dear!

I think it's a fair question if you're unsure!

The tighter the bend in the rope the weaker the knot is, so the overhand knot will be fractionally weaker than a figure of eight as it has a tighter bend.

(No knot in the rope being 100% strength)

Fig 8 knot  75% - 80%  so loss of 20-25%

Overhand knot 60% - 65% so loss of 35-40%

Thank you Pete.

Yes I was aware of the fact that there were strength differences between FofE and OH - interesting to see by how much though.

Cheers

I learnt to use a rethreaded overhand knot from a mountain guide (British), with the loop clipped back to your harness in lieu of tying a stopper knot. It's useful for tying in to the middle of a rope - e.g. in a guided situation.  I use it for tying in to the middle of a rope that's been doubled up (e.g. a half rope being used on a short route) - it's not as bulky as a Figure of Eight when you've got a double strand.

There's also the Alpine Butterfly for tying into the middle of a rope 

Hi both, thanks for your comments.

My preferred knot for tying into the middle is also the alpine butterfly but as others have stated on here using the overhand to tie into your harness is legit, if potentially difficult to untie.

I know, but I can never remember how to do it!

Very interesting.

How does the bowline compare? My brain can't decided if it has tighter bends that an 8? And would a double bowline be any different?

... all of which is pretty much irrelevant seeing as climbing ropes don't snap at the knot due to loads they experience in ordinary - or even extreme - climbing situations, regardless of the knot used. There's simply too much inherent strength for it to be a factor. If ropes fail at all it's due to abrasion or sharp edge damage, or potentially through chemical contamination or other misuse.

The test knot for certification used to be the overhand anyway, it was changed to the 8 for some reason.

A figure of 8 absorbs the energy of a fall much better than an overhand. So less force on the system. Overhand knots can also creep and come undone, although perhaps not in this situation.

AFAIK Figure 8 knots are actually more likely to creep, especially under ring load, but this is not the issue for tying in with either knot. Not wanting to rehash this here, this discussion has been done to death in a million threads on joining abseiling ropes....

CB

I use a re-threaded overhand to tie prusik loops.  its much easier to undo than the traditional double fishermans and means you can use it for abseil tat/abolakovs etc

I use an overhand (tied one handed on the two free ends together) for threads, standard practise in Czech and Saxon sandstone climbing. 

CB

Indeed - it took me an embarassing amount of time with a bit of cord to remember how to do it last night!

Another similar option but easier to untie if he's tending towards an overhand knot is a swami loop knot (sounds more fancy than it is...).

Tie a loose overhand knot 50cm from end of rope.

Pass working end of rope through tie in point,

Pass working end of rope through overhand (don't fully re-thread it, just poke it through),

Tie double overhand stopper around the standing end.

Quick to tie and neat, I often use it seconding easy routes.

Been thinking about this since last night and, if you're doing what I think you're doing, it's still quite a bulky knot. Have you got a pic of it anywhere?

Hi Andy,

Yes I have seen this knot before - I quite like it, interesting that you rarely see it being used though - at least in the circles I am in.

As with so many things in climbing I guess it comes down to your experience (whether or not you have ever learnt anything other than the fig8) and a force of habit - that's the case with me certainly.

Thanks

Irrelevant, apart from the fact that you have effectively weakened your rope. I think you mean that in most situations you are prepared to accept that.

Do you have a supporting link for that statement? Unless ropes are subject to falls the like of which they almost never receive, they will quickly recover their previous dynamic performance and hold-falling potential.

I'm also not entirely convinced that in extremely severe falls the knot is even the weakest link, as the bend through the krab on the holding piece may well be the critical potential point of failure most of the time. If that's true then it's another reason to believe the choice of knot not to be a strength-significant factor.

My point was that the relative strength of knots in climbing ropes is quite probably never in any way significant, despite such figures being frequently trotted out to imply that it might be.

Sorry, no photo, but I promise it's a lot less bulky than doing it with a Figure of Eight.

An interesting study on the strength of knots in climbing rope here: http://personal.strath.ac.uk/andrew.mclaren/alasdair_brown_2008.pdf 

I expressed myself badly: I did not mean to imply permanent weakening of the rope. Nor did I mean to imply that I thought the knot was necessarily the weakest part of the belay chain. Simply, that the presence of a knot reduces the breaking stress of the rope itself; some knots are worse than others in this respect.

Thank goodness modern climbing ropes are such wonders of technology and strength to weight ratio. And, as such, represent remarkable value for money compared with many items of outdoor clothing, for example.