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Some questions about rope swings similar in size to the the corona arch swing which has an accompanying setup video.

  • Assuming you can avoid rope abrasion, do swings like this damage climbing ropes? Swing goes straight into a pendulum with no/limited free fall.
  • The figure eights get very tight at the anchor. I've heard people say you should loosen them, retie them, or cut them away after several jumps. Any truth to this?
  • We set up a prussic chord at the anchor. It attached just below the figure eight knot that secured the jump line. This kept the weight of the jump partially off the knots. Are there risks associated with this - eg. can prussics weaken a system like this, or cut the rope?
  • We also jumped onto a prussic (primary), with an atc below, with overhand knot below that. We clipped the bite from the overhand knot to our belay loop. We did this because we jumped with a backpack and had to rapel to the ground after the swing completed. Slightly clustered, but we wanted to easily rapel after the jump was completed. Any feedback on this setup?

[EDIT] Removed some slang

  • This is an interesting question, but a bit unclear. Please clarify the following: "It bit just below the figure eight knot"; "(primary)"; "clipped the bite from the overhand knot"; "A bit clustered". I think these are typos or slang; don't know for sure. – anatolyg Jul 18 '16 at 9:35
  • Probably "bite" = "bight" – J Kimball Jul 18 '16 at 15:38
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    Potentially better to split this into multiple questions? – aaaaargZombies Jul 18 '16 at 23:34
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    @Liam A bowline can untie when not in tension which is extremely relevant for a jump like this. You'd need at least a double bowline, though that is still significantly weaker in cross load as shown in this video youtube.com/watch?v=jSms2k2eV3Y – Kenn Jul 19 '16 at 8:47
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    Providing you add a good "tail" and a stopper it shouldn't come undone. Remeber bowlines where THE tieing in knot not that long ago. A double bowline is a good option for extra safety – user2766 Jul 19 '16 at 9:27
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Assuming you can avoid rope abrasion, do swings like this damage climbing ropes? Swing goes straight into a pendulum with no/limited free fall.

I can't see it doing any special damage to the rope that wouldn't occur through climbing. I would make regular inspections of the rope and retire/replace equipment when necessary. The fall factors involved are well within the 1.7 tested by the UIAA but it might be worth contacting the manufacturer of the rope to see if they have any information about how the ropes perform in the pendulum type fall rather than a straight one.

The figure eights get very tight at the anchor. I've heard people say you should loosen them, retie them, or cut them away after several jumps. Any truth to this?

If you can't untie them then I guess you'll have to cut them. If this is happening regularly than maybe you can prevent it by undoing and retying so they aren't getting repeatedly tightened with each jump. I'd say if you can untie them then you don't need to redo them, your just adding more opportunities to make a mistake. If you find that the rope is becoming deformed or the sheaf is getting damaged then that part of the rope is no longer safe and should be cut out.

We set up a prussic chord at the anchor. It attached just below the figure eight knot that secured the jump line. This kept the weight of the jump partially off the knots. Are there risks associated with this, eg. can prussics weaken a system like this, or cut the rope?**

A figure of 8 is a very efficient knot, retaining about 80% of the ropes strength. I don't know of any figures that show the efficiency of a adding a prussic to a rope but I doubt it is making the system stronger. It is also just another way to add a point of wear to the rope. Lastly what are the prussics attached to? surely loading the weak prussics instead of the strong rope is not desirable. I would personally avoid doing this.

We also jumped onto a prussic (primary), with an atc below, with overhand knot below that. We clipped the bite from the overhand knot to our belay loop. We did this because we jumped with a backpack and had to rapel to the ground after the swing completed. Slightly clustered, but we wanted to easily rapel after the jump was completed. Any feedback on this setup?

Again is the prussic on your harness directly loaded in the fall? You want to give yourself the widest safety margin you can so that would look more like clipping into a figure of eight with a carabiner designed to avoid cross loading. Prussics and ATC on the harness ready to use once you come to a stop.

Caveat: This isn't the way to swing on a rope more a critique of your current set-up from a climbing perspective.

  • We just sort of combined climbing knowledge with conjecture and doubled things up when in doubt. I feel like everybody just focuses on the anchor in other online discussions; but then when I went to actually set things up I found there were many other sources of doubt in the system. Is there a "best way" to set up a swing like this? – Kenn Jul 19 '16 at 5:50
  • @Kenn You really need to split your questions up. This follow up question of how to setup an ideal swing system is a great question. Almost any single question you put in the question at the top is a good question that should stand on its own. You will also get more answers when you split them up. Now one needs to have an answer to every single aspect in order to write up an answer, however many people will have valuable inside on at least one of them. Please split the question up, aaaaargZombies's answer can be ported. – imsodin Jul 19 '16 at 9:37

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