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/ Abbing off long pitches

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Sam B on 12 Jan 2019

What's the best practice for abbing off 35m+ single pitch sports climbs, with a 60m lead rope and a static/tag line of the same length?

Obviously I'm looking to end up with the two ropes tied together with an overhand bend, the lead line passing through both staples, and my normal abseiling rig on. But the only way I can think of getting there that doesn't involve unnecessary single points of failure or risking dropping ropes is a bit of a faff.

Is there an 'official' way of doing this? Is it the obvious way, or am I missing something simpler?

Thanks very much for any tips.

Duncan Campbell - on 12 Jan 2019
In reply to Sam B:

Buy an 80m rope?? Then go about as you normally would, threading the belay and being lowered off by your partner?

Luke90 on 12 Jan 2019
In reply to Sam B:

I've not had to use a tag line but my inclination would be:

  1. Have the tag line clipped to my harness with enough slack left in the end to tie the overhand bend
  2. Pull up a bit of slack on the lead line and clip it to my belay loop with a krab (by a clove hitch or a figure eight on a bight or whatever knot you fancy)
  3. Untie lead rope from harness, thread it and tie it to the tag line
  4. Attach abseil device
  5. Unclip and untie the now superfluous attachments to lead and tag line

Is that what you had in mind as the obvious method that seems too faffy? It doesn't strike me as all that much worse than threading an anchor normally and I can't see that it could be streamlined all that much.

Dave Cundy - on 12 Jan 2019
In reply to Luke90:

That's what I'd do as well.  Only takes a minute.  Mind you, I think I'd prefer to use a double fisherman's knot as it's well suited to two ropes of different diameter.

The last time I did this in anger was in Sardinia.  I took my 30m climbing wall rope and a 15m tag line (yes, a bit longer would have been more useful!).  But it kept me happy for a few hours while my other half was on the beach.

JohnV - on 12 Jan 2019
In reply to Sam B:

What about threading the clean end of your lead rope through the staples, then tying a bulky knot which cannot pull back through the staples (double figure of 8, or monkey fist... I’m joking). Then tie your tag line to the loop of the double figure of 8, rap on both. 

I’ve not used a tag line, but this is what was in my head when thinking about rapping using one...

john arran - on 13 Jan 2019
In reply to Sam B:

Possible confusion here in the use of the term 'tag line'.

A tag line is usually not thick enough to be a load bearing part of the abseil, it's job is purely to pull the single rope after the ab is done. As such, tying the two with an overhand, as if it was a second lead line, doesn't make sense.

What's more normal is to tie a fig 8 on the bight in the end of the lead line once you've threaded it through the anchor, then use a krab to clip the loop back to the main lead line. The tag is then tied either to the krab or (better) directly to the lead line knot so it can be used to pull down the knot and krab, thereby pulling the whole lead rope through the anchor.

Plenty of references online if in doubt.

HeMa on 13 Jan 2019
In reply to Sam B:

Thread the anchor as you normally would. Tie a fig 8 on a bight After the anchor and tie the tag line to the bight. Clip an extra biner to the bight and then on the main rope. Attach grigri/atc to the main rope. Remove safety backups & rap down on the main rope. When at the ground, pull rope with the tag line. 

Sam B on 13 Jan 2019
In reply to Duncan Campbell:

> Buy an 80m rope?? Then go about as you normally would, threading the belay and being lowered off by your partner?

Thanks, I can see that could work, but I'm not sure where I'd find one out here! 

Sam B on 13 Jan 2019
In reply to Luke90:

Yeah, that's what I was thinking. You do end up with a lot of slack in the lead line to pass through the belay plate and prussik, but it's not the end of the world. Thanks for your help! 

Sam B on 13 Jan 2019
In reply to john arran:

Thanks for that, the diameter difference isn't so much, but it's worth thinking about. Probably best to play it safe, even if it means a bulkier knot.

Thanks very much for your help. 

Sam B on 13 Jan 2019
In reply to HeMa:

Yeah, think that's possibly the best way. Was thinking about tying them together with an overhand bend, but I'm not so sure now.

Thanks for your help! 

Sam B on 13 Jan 2019
In reply to JohnV:

Sounds like maybe it's better to clip the knot to the loaded rope? So it doesn't get stuck in the staple or roll over, presumably.

john arran - on 13 Jan 2019
In reply to Sam B:

> Thanks for that, the diameter difference isn't so much, but it's worth thinking about. Probably best to play it safe, even if it means a bulkier knot.

That makes it sound like it isn't a tag line so much as a slightly thinner second climbing rope. In which case I definitely would ab on the two together, having tied them with a simple overhand as in your OP. Differences in diameter of up to a couple of mm don't make a lot of difference at all to the knot, and if you're really concerned you can put a second overhand in the tails of the first, tucked up tight against it. The big advantage is the greatly reduced chance of the knot/krab getting snagged on anything when you come to pull it.

The other consideration would be that you have a belay device that works reasonably well with both of the ropes you're using, but most devices are pretty good with a good range of rope diameters nowadays and the issue of knot creep while abbing is usually overstated. If you have 2 rated ropes and a belay device that works with both, better to ab on both together. Otherwise the tag-pull method is very useful to know.

oldie - on 13 Jan 2019
In reply to john arran:

> ,,,the tag-pull method is very useful to know. <

Possibly also worth noting that often one has a a good length of climbing rope unused in the tag rope method which can be used as the upper part of the tag line if need be. In the OP example of 60m rope with 35m to ab the tail from the knot on the bight at the anchor could be 25m (obviously must be sure main section still reaches ground), Only the bottom part needs to be dedicated tag line (about 10m in this case) which could be eg general purpose polyprop cord (this could even consist in part of a chain of tat and slings in a trad situation).

Rick Graham on 13 Jan 2019
In reply to Sam B:

One way to avoid single point failure risk.

Assuming say 40m pitch and 60 m rope, climb route as normal and lower off down to half way, rope now tight to belayer who is tied in.

Leader clip into bolt, retie into rope with double bowline or overhand/fig 8 and two screwgates, untie from end and pull through.

Now abseil on "spare" rope, either direct through hanger or a maillon (which may be retrieved later if doing adjacent route) , belayer now takes in to protect leader and pull into bolts if route steep.

All leader has to carry extra is ATC, a few krabs and a maillon.

If multiple abs are done, in theory , depending on bolt spacing,  you might even get away with a 50m rope on a 40m sports pitch, though a few more tricks may be required to minimise potential falls if a single bolt failed.

Stairclimber on 14 Jan 2019
In reply to Sam B:

If we are talking about using extra climbing rated rope rather than tag line to enable descent from a slightly longer sports route, why not be lowered off as normal, stop and clip into a bolt on the way down while your belayer passes the knot that joins an extra piece (your own 10m say) or end of someone else's nearby climbing rope? This knot will not pass through your first quick draw, so pull up the end and drop to your belayer before he joins the two ropes. 

This will get you out of an unexpected shortness of rope if being lowered and  your rope ends while you are still 3 bolts short of the ground. You could for example ask to briefly borrow the extra length required from the unused rope piled up on a neighbouring climbers rope mat. Or you could plan to carry some extra rope if you wanted to use a rope that you knew wasn't long enough for a particular route. 


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