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I have a fixed vertical line that can be ascended/descended. I need a bag (a bucket with tools, actually) when I'm hanging mid-air, and need to move it up/down. The bag is over 20 lbs / 10 kg so I definitely don't want to attach it to me!

This is what I invented, using a separate haul line. It works but it's not very comfortable to use and maybe there's a better (and safer) way to do it?

Principle of operation

The load is locked in place with a prusik. When I want to move the bag, I pull on the secondary prusik loop, release tension from the main prusik and slide it up or down, then tend to the "pulling prusik". Repeat as required.

My rig

Pros

  • Simple
  • Easy to rig
  • No special equipment required (a pulley can be replaced by a screw-gate)

Cons

  • You need to pull the whole weight of the bag each time you want to move
  • When you're tending the main prusik, the bag's weight is held by a hand/foot in the pulling loop; if you let it slip, it would be ugly (fingers jammed / the bucket shoots up and probably spills over its content)
  • Lowering the bag is not very gradual (sometimes it's shock-loaded if I release the pulling loop too quickly)
  • Disassembling the rig is tedious (you need to pull the bag all the way to the top, dock it, untie prusik, clip it out from the biner, then belay the bag down). A simpler option is to lower the bag with prusiks to the ground and then untie the prusik, but that's not always feasible.
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  • Maybe I'm missing something, but aren't your issues addressed simply by feeding the rope through a grigri, which is attached to the anchor?
    – user2169
    Commented Apr 21, 2021 at 17:04
  • Hi @BenCrowell, I don't own a grigri (my instructor taught us that They are the Work of the Devil, are Considered Harmful and should be shunned :)). Anyway, in my understanding, when using a grigri you need to pull a lever to unblock it, am I correct? And I'm far away from the anchor, I won't be able to reach the grigri...
    – Alexander
    Commented Apr 22, 2021 at 9:29
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    Fix the tedious disassembly by adding another carabiner between the "prusik" and "load". Fix the "pull whole weight of the bag" by adding advantage-- You want to control the height from a position near the bag, not hauling from the top or bottom, right? Then grab a bight of line above the "prusik" and put it in a pully (locking, non-locking, or devil GriGri) attached to "load" and pull upwards as a 3:1 rigged on the load rather than at the anchor. (you may need to move the prusik attachment further up "haul line" to hold captured progress upward.)
    – Dave X
    Commented Apr 22, 2021 at 15:24
  • Great idea about secondary carabiner for disassembly, thanks @DaveX! I'll try the advantage... although I feel that PULLING UP is less convenient and might be awkward, as compared to a simple pull down. BTW from what I remember, this kind of rigging gives you a 2:1 advantage, NOT 3:1, right?..
    – Alexander
    Commented Apr 23, 2021 at 10:35
  • It depends on how many lines are pulling up on the load -- Ignoring friction, pulling up gives you the one in your hand, the one coming down from the pulley to the grigri, and the one from the load going up from the load to the pulley, all three sharing the 1/3 of the load. If you pivot the GriGri around to pull down, it isn't lifting anymore, and you only get the 1:1. If you want a 2:1 pull down, start at the anchor, put a pulley on the bag, go back up to the anchor through a turning pulley, and come back down to your hand/progress capture. This 2:1 takes more line and is more tangle-prone.
    – Dave X
    Commented Apr 23, 2021 at 15:54

2 Answers 2

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Raising

You can improve your system by adding a pulley to tend the Prusik knot. The pulley is placed on the running side of the rope below the load-bearing Prusik, and is then connected to the load-side of the rope and lifts the Prusik along with it. This lets you raise the load by pulling on the rope with both hands.

ClimbingArborist.com illustrates how to use this (for rope ascension) in a four minute video.

enter image description here

A 20 second video for the the impatient.

Lowering

As shown in the video above you should be able to lower the load by only releasing the Prusik with control; you should NOT have to use the "pulling loop" to unweight it. If you do have to unweight it you should use a different friction hitch, or a different cord to tie it.

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I don't own a grigri (my instructor taught us that They are the Work of the Devil, are Considered Harmful and should be shunned :))

Your problem seems to be that the method of progress capture you're using, with a Prusik, is awkward and inconvenient. A GriGri is a standard tool for this purpose.

And I'm far away from the anchor, I won't be able to reach the grigri...

If your goal is to get the haul bag up to the anchor, then climb to the top, tie in to the anchor, and then raise the bag from there.

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  • Ben, I still don't understand how could I LOWER the bag while hanging mid-air without having access to the grigri installed at the anchor. Can you please explain?
    – Alexander
    Commented Apr 22, 2021 at 13:19
  • If it was just about progress capture, I'd use a progress capture pulley... the problem is — I need to move the bag UP and/or DOWN while hanging on the rope.
    – Alexander
    Commented Apr 22, 2021 at 13:20
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    Wait hold on. I think I'm getting it now. You mentioned first that a grigri should be installed at the anchor; maybe what you meant was "a grigri should be used instead of a prusik, in exactly the same configuration as on the drawing"?.. Then a grigri will be at my height and I might manipulate it... would that work?
    – Alexander
    Commented Apr 22, 2021 at 13:54
  • I'm saying to go to the anchor and perform the whole operation from there. Don't try to accomplish all this while ascending the rope.
    – user2169
    Commented Apr 23, 2021 at 1:36
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    Yes, Ben's answer can help, even if you don't go to the anchor. Replace the prusik in your diagram with a GriGri to simplify the progress capture (and disassembly).
    – Dave X
    Commented Apr 23, 2021 at 16:00

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