Stone Knot as a contingency

[ratagonia]

When I saw this done the rope was biner blocked. Before they started lowering they tied a fisherman knot with the original rappel strand right above the tibloc in case it slipped?


Mark

It is still hard on the rope where it goes over the edge. Might not slip and fail, might mess up the rope.

Tom

[Slot Machine]

Steph and I were playing around with this conversion today, we got it done in 1:56.



Special thanks to my wife for being the victim in this video.

[ratagonia]

ooops. Emi did not like you pirating their music. Sorry dude.

Please post again.

Just a quick comment: when you add the rope going over a rock edge, it increases the force required for the lift substantially.

Just saying - your time does not count unless it is over a rock edge...

Just like the badminton players - was that in the rules???

Tom

[Slot Machine]

Fixed.

Just saying - your time does not count unless it is over a rock edge..

Meh.

Bob

[ratagonia]

Now it says "removed by the user"... ???

T

[Slot Machine]

Bah! Works fine... until I walk away.

There, nowwww it should work.

[Brian in SLC]

Should probably add some penalty points for not backing up the rappel line prior to un-doing the stone knot...

Fun stuff...thanks!

[ratagonia]

Bah! Works fine... until I walk away.

There, nowwww it should work.

Looks good - very nice. (Video working now).

Good clean process. And, I think you can see that another 0:15 could probably be gotten out of it. I like the ropegrab on the harness.

No penalty points in my book for "not backing up...". To me, a ropegrab under continuous tension does not need to be backed up.

Tom

[Brian in SLC]

No penalty points in my book for "not backing up...". To me, a ropegrab under continuous tension does not need to be backed up.

You have a person's live weight and life on a "rope grab" with no back up? Toss a quick clove hitch on a biner, clip to anchor, takes two seconds, and, if for some reason, like when you twist sideways whilst leaning back and the "rope grab" slips or worse, then your live person won't get creamed.

Me? I'm recommending a backup as a standard protocol before weight transfer to a "rope grab" and undoing the Stone knot.

Wearing a helmet is a personal choice, however...ha ha.

[Slot Machine]

Should probably add some penalty points for not backing up the rappel line prior to un-doing the stone knot...

Fun stuff...thanks!

Brian, that is good suggestion. Dropping the rope "over the edge" would have been really bad. I'm assuming you don't think the ropegrab was going to fail.

Looks good - very nice. (Video working now).

Good clean process. And, I think you can see that another 0:15 could probably be gotten out of it. I like the ropegrab on the harness.

Tom

Thanks! If Steph was infinitely patient and our son would just nap all day, we could have shaved off an exra 0:15. It could have been our Olympic qualifying time.

Bob

[Slot Machine]

You have a person's live weight and life on a "rope grab" with no back up? Toss a quick clove hitch on a biner, clip to anchor, takes two seconds, and, if for some reason, like when you twist sideways whilst leaning back and the "rope grab" slips or worse, then your live person won't get creamed.

Me? I'm recommending a backup as a standard protocol before weight transfer to a "rope grab" and undoing the Stone knot.

Wearing a helmet is a personal choice, however...ha ha.

I was using a Basic as a ropegrab. It would have taken an act of God to make it slip IMO. Maybe if using a prussic as a ropegrab... yeah I could see that slipping.

Either way, due to slippage concerns, or just to keep the rope from falling over the edge should you drop it, it should be backed up.

[Brian in SLC]

I was using a Basic as a ropegrab. It would have taken an act of God to make it slip IMO.

Yeah...an act of dog...

Improper loading can prevent the ascender from grabbing the rope

The ASCENSION and BASIC ascenders are designed to be loaded in a direction parallel to the rope; if loaded at an angle to the rope, the cam may not correctly engage the rope and slippage can occur (See the technical notice, diagram 2).

Having one person, the person who is ascending, or, hauling, minding an ascender is one thing...but...having a live weight on the other end...for me, would require a back up. Heck, if I was on a wall and hauling, and, had to unweight the rope from a haul bag, I'd secure the thing before I transferred the weight onto an ascender. But, a person? Oh yeah.

[Slot Machine]

Forget what I said about the rope falling over the edge. It is tied in during the entire process.

Anyway, I'm with Brian on this one, live person, backup, good idea.

For the sake of learning a bit more, I'll play the devil's advocate for a moment:

Brian, I can't imagine the Basic slipping if weighted, even if twisted, as long as the direction of the force is in-line. On my rigging, all of the force is in-line. (is it not?)

Have you had an experience where an ascender or rope grab has slipped?

[Brian in SLC]

Have you had an experience where an ascender or rope grab has slipped?

Yeah, a number of times. I schredded the sheath on a rope doing a practise raise with a tibloc. I think I've posed photo's of it before. Real similar to how you'd unload a stone knot.

I've done a fair amount of jugging on fixed lines for aid climbing, etc. I've had side loads or whatever cause handled ascenders to slip.

Kinda the way I see it, if you need to convert to a lower in the field, for real, the anchor location, the environment, the situation, etc, might not be pretty. A back up prior to "going live" is fast and easy. Should something go wrong for whatever reason, not much harm done. The consequences of losing a live load could, and most likely would, be very severe.

I can't imagine transferring someone's weight, and mine, at the same time, all hanging in the balance off a single "rope grab", with no back up. Especially when a quick and simple back up is easily available.

[hank moon]

Kinda the way I see it, if you need to convert to a lower in the field, for real, the anchor location, the environment, the situation, etc, might not be pretty. A back up prior to "going live" is fast and easy. Should something go wrong for whatever reason, not much harm done. The consequences of losing a live load could, and most likely would, be very severe.

Attachment 57253

A lot of what we do is influenced by habit. If I train without using a backup, I'll probably be less likely to install one when it's a good idea to do so. I might become habituated to my favorite technique "always working" and become blind to its potential failure modes. I imagine that even Tom might install a backup under certain circumstances. That said, when a proper ascender is properly loaded (on a proper rope), it should not slip...any more than a carabiner will spontaneously break.

[Brian in SLC]

Totally agree with that, Hank.

I've got in the habit, even on 40 foot long sport routes, of putting a bite into the blunt end of the rope. Its just a habit, but, like you said, those types of habits can be the difference when things don't go as planned.