/ Anchor set-up (MS Paint diagram)

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Taurig - on 12 Apr 2012
Hi, myself and a mate would like to progress from the indoor bouldering wall to some outdoor climbing, and we have a local crag that seems suitable for some top roping (belayer at top, not bottom). Unfortunately we don't know anyone that can teach us, but I've been studying the Libby Peter book, reading threads on here, and with a good dose of common sense I'm hoping we should be OK.

So one of the routes we want to top rope has an absoloutely solid tree as an anchor, but its about 10m back from the cliff edge. At first I thought about using a 240cm sling around it and clipping the climbing rope in, but the tree is pretty big and I think the angle at the sling would be way over 60 degrees. So my next thought was using 20-odd metres of static rope around it, in conjunction with a sling round a smaller anchor nearer the edge. I have produced this stunning MS Paint diagram of what I was planning on setting up (missing out belay device etc. for the moment).

http://i10.photobucket.com/albums/a119/MarkDH05/Anchor1.jpg

I was wondering if anyone could say a) if this looks like a decent set-up and, what was also concerning me, b) is the reef knot with double stoppers a good way of joining up the ends of the static rope? I thought it would be best to effectively make a big sling out of it but wasn't sure on the best knot to do so, I thought the overhand knot might suffer if the ends were pulled 180 degrees?

Thanks for any help.
Monk - on 12 Apr 2012
In reply to Taurig:

The set up looks ok (lovely drawing, BTW). In theory the reef knot + stoppers should be fine, but is takes a while to tie. It would be simpler to tie a bowline around the tree then just have a single strand coming to you - you don't need to create a sling.
Al Randall on 12 Apr 2012
In reply to Taurig: I wouldn't use the length of static rope as this is not something that most climbers would normally carry. Put a sling round the tree with a screwgate krab. Avoid larksfooting it unless it is likely to slip off. Clip the climbing rope into the krab and screw it up, walk back to the edge and with another screw gate clipped into the loop created by tying in tie a clove hitch or F8 into this krab. If the tree is a good one I wouldn't bother with a back up on the second tree. It is also possible to do a similar belay just using the rope but it is harder to judge the length of rope required without a bit of experience. The advantage of this method however is that you just need rope and if you do need a second attachment the loop created after a couple of half turns will clip into this.

Al

mike kann - on 12 Apr 2012
In reply to Taurig: You don't need the static rope - the clove hitch at the solid anchor isolates any potential movement in the rope - you can just take the rope from your harness back to a shorter sling around the tree with knot, then back to the secondary tree, knot, then back to your harness. The secondary tree is useful as it will help reduce the amount of rope stretch you will experience when your buddy falls off. Make sure the rope back to the main anchor takes the main load though i.e. it is tight when you are in your belay position.
Fredt on 12 Apr 2012
In reply to Taurig:

What I would do is, (assuming I am still tied into the rope) walk around the tree, back to the edge. Put a clove hitch in the rope that is going down to the other climber and clip that to my harness loop, so just creating 1 big sling with the rope, adjust clove hitch so my big rope sling is tight. No need for slings around the tree.

This set up is always my belay of choice, round boulders, rocks or pro in the rock. With artificial anchors, I'd do it twice.

Needs 1 krab. Keep It Simple, Sir.
jkarran - on 12 Apr 2012
In reply to Taurig:

Looks fine but more complicated than need be.

Scenario a: Tree a few meters back and a fat climbing rope... Tie the end of the rope to the tree (stoppered bowline or rethreaded fig8 are both easy). Tie a fig8 on the bight (OTB) a foot or so back from the edge, clip yourself to it then throw the spare rope down to your partner. Belay off the loop you're clipped to.

Scenario b: Stretchier rope... Tie in, walk back from the edge, around the tree and back to the edge. Clove hitch (or fig OTB) harness krab to the rope to close loop around tree. Sit down and belay off your harness.

In both scenarios you can add a second anchor very easily. While one good tree is good enough you should aim for a minimum of two pieces to begin with at least just in case you miss something.

Make sure belay ropes are snug, disappearing over the edge on stretch isn't nice. And be very wary of rope rub especially where the rope is fixed but rubbing rather than running, wear concentrates in one spot and you can destroy a rope in minutes. Pad edges with trainers, rucksac etc

Have fun,
jk
Al Randall on 12 Apr 2012
In reply to Fredt: You could make it simpler by not using any krabs but a krab makes adjustments easier. Sometimes the main rope round a big tree just locks up and you have to go back and forth until you get the length right.

Al
Taurig - on 12 Apr 2012
Mike and Al: It would certainly make things simpler if I didn't have to buy some static rope, and my first thought was to do as you suggest and just run a sling round the tree and clip into that. However, as I mentioned above, the tree is quite substantial (trunk is probably about 1m in diameter)and so bombproof, but I was concerned that the angle of the sling might be too wide. I keep reading that you should keep the lines of an anchor at 60 degrees or less, or am I being a bit overcautious here?
Al Randall on 12 Apr 2012
In reply to Taurig: Then do as Mike suggests with the climbing rope, it's just that with slings and krabs minor adjustments are made easier. I have never carried "static line" and I can't think of many situations where a 240cm sling would not go round a tree. You are of course correct about minimising the angles however.

Al
Voltemands - on 12 Apr 2012
In reply to Fredt: + 1. Simple is good.
JLS on 12 Apr 2012
In reply to Fredt:

>"walk around the tree"

Paying out the rope as you go to avoid dragging 10m of rope over the tree bark. You wouldn't want to damaged a tree, would you... :)
Taurig - on 12 Apr 2012
OK, so I have modified the original as suggested above, assuming that I wanted to use both anchors (it's probably overkill for top roping a VDiff but I'd rather be safe than sorry...). Is this OK?

http://i10.photobucket.com/albums/a119/MarkDH05/Anchor2.jpg

I've read that two clove hitches even on a big HMS krab might be too much, so if this is the case I'd just use two screwgates on my rope loop, one for each anchor.
jkarran - on 12 Apr 2012
In reply to Taurig:

Spot on.
jk
Taurig - on 12 Apr 2012
In reply to jkarran:

Fantastic, I'll give it a shot in the garden first just to get the hang of it, cheers everyone for the advice! :)
The Ex-Engineer - on 12 Apr 2012
In reply to Taurig: The two solutions I would use for top-roping with a far away anchor in this situation would be:

With a static rigging line:
You produce a centre point with the static rope forming a 'V' from the two anchors with the centre point, ideally around 1 metre BACK from the belay position and cliff edge:
- With one end of rope tie a bowline around the large tree (with stopper knot).
- Measure out length of rope required down to centre point position (adding around 20cm for knot) and then back to 2nd tree.
- Clove hitch onto a screwgate on a sling around the 2nd tree.
- Tie a Fig-of-8 on bight (with small loop) to create the centre point (going back to adjust the clove hitch if required).
Now you tie into the end of the climbing rope, clove hitch your rope to the centre point and FOR THE FIRST TIME approach the edge of the cliff and then do any fine adjustment you require via the clove hitch, which should nicely be in reach. You are then ready to drop the end of the rope and belay.

Using just the climbing rope:
- Tie one end of the rope to the large tree with a bowline (and stopper knot).
- Clip the rope into the krab on the sling round the second tree.
- Put a prusik onto the rope going to the large tree and clip to your harness with a short sling to provide for your safety.
- Take hold of both strands of the rope leaving the krab at the second tree.
- Keep hold of these two strands and walk to where you are going to belay, allowing the ropes to slide through your hands (and moving the prusik if needed)
- Allowing for an extra 20cm for the knot, tie an overhand knot on the bight using both strands of rope to provide a centre point in the perfect position to belay from.
[If you have done this properly you will have an overhand knot with 4 strand coming out the bottom, on going to the large tree, two going to the second tree and one which is the remainder of the rope.]
- Clip yourself into the centrepoint with a screwgate to your belay loop
- Clip your belay krab and belay device into the centrepoint and you are then ready to drop the end of the rope and belay.

The first solution is one I would strongly recommend you study. As already mentioned by several other posters, using a bowline to connect one end of a rope to a far away anchor is a fairly basic and useful technique (not to mention being quick to tie and easy to undo after loading).

The second solution is admittedly using a rather more advanced technique on the sort more used by instructors, but it is UKC and you did ask...
The Ex-Engineer - on 12 Apr 2012
PS The solution in your second diagram is perfectly safe and very workable.

The only downsides are that will use a fair bit of rope and be a bit awkward to adjust, however that is probably a very fair compromise for keeping things fairly simple and easy to understand.
Taurig - on 12 Apr 2012
In reply to The Ex-Engineer:

Thanks Ex-Engineer, I would agree that the second method is a bit more complex and I would probably end up cocking some part of it up, but the first one seems pretty good if I had some static line to work with.
ChrisJD on 12 Apr 2012
In reply to Taurig:

I'd get a harness that fits. Your legs and waist look undersized for the harness you have.

And lying down with no hands on the rope is considered bad form. As is smiling.

A belay device on the live rope might also help.

NIGBEE on 12 Apr 2012
In reply to ChrisJD:

Be aware that the weight on the belayer feels a lot heavier if you are belaying from the top rather than bottom roping (pully effect)

If you have only belayed from the ground before at the indoor wall you may get a shock if you lower your mate off from the top

Ace pics BTW
Mark Reeves - on 12 Apr 2012
In reply to Taurig:
> I've read that two clove hitches even on a big HMS krab might be too much, so if this is the case I'd just use two screwgates on my rope loop, one for each anchor.

Too much for what? Not only fairly industry standard, but commonly used and most of us have survived. The loads in this system would be fine unless you take a factor 2 fall onto it, and even then i am not sure the forces would impact this.

two clove hitches might weaken a carabiner by provide more leverage, but that should make the system life threateningly dangerous. I bet the carabiners test still break above 11kn, which is stronger than most wires.
CurlyStevo - on 12 Apr 2012
In reply to Mark Reeves:
Personally I use figure of eights on the bight back to my tie in loop as it reduces the need for extra screw gates and I actually find it faster (but I am profficient at the method).

It's quite hard to generate a large force at the belay as the belay plate slips at 2-3kn. Either the climber must factor 2 fall when there is no more rope to pay out or the belayer factor twos once attached to the anchors.
Taurig - on 12 Apr 2012
In reply to Mark Reeves:
> (In reply to Taurig)
> [...]
>
> Too much for what? Not only fairly industry standard, but commonly used and most of us have survived. The loads in this system would be fine unless you take a factor 2 fall onto it, and even then i am not sure the forces would impact this.
>
> two clove hitches might weaken a carabiner by provide more leverage, but that should make the system life threateningly dangerous. I bet the carabiners test still break above 11kn, which is stronger than most wires.

Just going by what the book I have says, which is 'A large HMS karabiner may be sufficient to seat two clove hitches but if there is any concern about creating a load too wide for the karabiner, two seperate screwgate karabiners should be used in stead'. I'm not entirely sure what it means by 'a load too wide' either to be honest, thought maybe if theres not enough space it might crossload under a fall?

Dave Ing - on 12 Apr 2012
In reply to Taurig:
Your second setup looks good. Just watch out for your nuts if your mate takes a lob because the rope tightens quickly, I tend to create a power point above me (where all the ropes meet on a locker or in a knot) for that reason and then do a direct belay with the belay device attached to the power point. I'll try to do you a photo.
jkarran - on 12 Apr 2012
In reply to Taurig:

> ...I'm not entirely sure what it means by 'a load too wide' either to be honest, thought maybe if theres not enough space it might crossload under a fall?

I presume that refers to a significant 3 way loading; Applying signifcant load along the minor axis. While it's clearly not ideal I confess it's not something I worry about in a top-rope set-up, if I'm using a krab at all (rare) I just keep ramming knots/rope onto it until I can't get any more on! <shuffles guiltily awaiting rebuke>

jk

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