Releasing from Loaded Guide Mode: Reliable Techniques?

Bill Lawry wrote:

In theory, the failure we saw could happen with two strands.

Very interesting, now that's something new. I can't visualize how it happens with two strands, would you be able to take some photos to show this?

aikibujin wrote:

Very interesting, now that's something new. I can't visualize how it happens with two strands, would you be able to take some photos to show this?

 sure. Although I may not have each strand loaded with a climber. Still, I think what can happen will be clear. Might get to this in a day or so.

Bill Lawry wrote:

 sure. Although I may not have each strand loaded with a climber. Still, I think what can happen will be clear. Might get to this in a day or so.

Any of us thank you yet for all the work you are putting into this?

Thanks!

Best, H.

Releasing from loaded guide mode:

1. Form MMO (Munter Mule Overhand).
2. Form a technical ledge.
3. Untie the guide plate's MMO. Note! Friction hitch is not a belay, so keep a braking hand on the braking strand to keep your partner on belay.
4. Redirect the load to the technical ledge and feed just enough slack. Keep your braking hand on the braking strand! Form MMO.
5. Now your partner weight is held by the technical ledge, the belay is guaranteed by the guide plate with MMO, and you have a couple feet of slack in between.
6. Form a Munter hitch with MMO using the slack in between technical ledge's friction hitch and the guide plate.
7. Now your partner weight is held by the technical ledge, the belay is guaranteed by the Munter hitch with MMO, and the guide plate is of no use, remove it.
8. Untie the technical ledge's MMO and redirect the load to the Munter mule + MMO. Remove the technical ledge.

Note. Keep everything as compact and as organized as possible.

Note 2. Do not forget about why knot if forming the technical ledge using a cordalette.

Daniel Joder wrote:

Ted, that has been my (very limited) experience, too, although I need to experiment with other diameter ropes/biners and different scenarios. I have found this thread very interesting and educational. However, I have found myself wondering if many of the recommendations to "never lower without a backup" are mostly recommendations left over from the more ON/OFF devices that were the norm before the Pivot came along. That is, they come mainly from folks who have not yet lowered with a Pivot to see and feel the difference. That is part of what I am still trying to decipher by following this discussion.

Yep, that's it precisely.  Traditional designs with a rigid autoblock hole don't allow for a gradual release, so the switch is sudden and abrupt.  This means that you need a backup (friction hitch) and a mechanical advantage (redirect), otherwise you can have rope sailing through the device, nasty rope burns, and an injured or dead second.  The Pivot eliminates all of these problems by using a flexible autoblock hole that allows the device to...well, pivot, gradually releasing the block.  It's genius.

Ted Pinson wrote:

The Pivot eliminates all of these problems by using a flexible autoblock hole that allows the device to...well, pivot, gradually releasing the block.  It's genius.

So I’m not going to go out and buy a Pivot no matter how much you try to sell it. I like my current device well enough and I can lower someone just fine with it. However, I am a curious and analytical person, so I try to understand why the Pivot works so well for lowering. The difference between a Pivot and other guide devices is pretty minor really, just a pivoting attachment point. But I don’t think the Pivot works better simply because it can pivot on the attachment point. Other guide devices can pivot on their attachment point too, so why don’t they work as well for lowering? One reason could be with the device weighed by a climber, there is a lot of friction between the attachment point of the device and the biner used to hang it from the anchor. But if that’s the only reason why other devices don’t work as well, then can’t you hang them with a DMM revolver biner and get the same smooth action as the Pivot? I intend to test this when I get a chance, but my guess is it’s not so simple. I think there’s another reason why the Pivot works, is that the pivoting point is lower than the attachment point (closer to the rope). This reduce the lever arm between the rope and the pivoting point, makes it easier to lift and control. I think this reduction of the lever arm is the primary reason why the Pivot works, not just because it can pivot on the attachment point.

 The magic of the pivot is not in the pivot itself but the fact that it reduces the lever by about 30%. This requires quite a bit less energy to open the device by providing more leverage for the belayer.  The closer the climbers weight is to the pivot point the easier it will be to lever up.

Bill---I'd be interested to see pics, too. It's well known about the risks of a GiGi/Ovo and single strand of rope "flipping," but I haven't heard of this particular mode of failure---pics/video would be helpful! I think some manufacturers' 8.9mm ropes are substantially skinnier than others'....it's definitely more "heads up" when using the devices at the margins of their parameters....

Here's my post from years ago about the GiGi and the potential of flipping on a single strand: http://www.elevationoutdoors.com/the-kong-gigi-totally-cool-if-used-correctly/ (Also, pages 80-81 in the book cover this topic...)

As for the DMM Pivot---I own one but have semi-retired it. On my first test-run with it, I had it slip a bit with a new 9.2mm Edelrid rope---the climber was just leaving the belay approx 30m below me...he stepped up, slipped and lost his footing...rather than locking firmly, the device slipped enough rope through it that the climber dropped about a meter onto the belay ledge. I suspect, due to distance/rope stretch, the device didn't get an immediate load and "oozed" some rope through...nevertheless, I'd never had an ATC Guide or Reverso do that, so lost some faith in the device. I also find the pivoting "ear" a pain when using the device as an ascender. We often teaching flipping a plaquette into "guide mode" when on rappel if one wants to ascend the rope. I find the pivoting ear makes ascending awkward and fumbly....but you guys seem psyched on the Pivot, so maybe it's worth another look? 

rgold--wow, thanks for the kind words! sincerely appreciated! people "follow" your posts and this will help with the book! 

Daniel---given how many accidents I've heard of lowering with guide-style devices (and given how much different carabiners and ropes, not to mention individual stances can affect lowering/friction), I'd err on the side of a backup when lowering. 

Somebody on the previous page was surprised by the advanced topics in the book---ah, yes, indeed! Sorry, sounds like you purchased the book expecting a bit more basic instruction---I encourage you to hang on to the book and refer to it when you can, but grab a more foundational read for the time being...and come back to the MGM when it's appropriate! But thanks anyway for the purchase and support! We appreciate it! 

Dang - and I was hoping to get a "second-hand" book cheap. ;-)

aikibujin wrote:

So I’m not going to go out and buy a Pivot no matter how much you try to sell it. I like my current device well enough and I can lower someone just fine with it. However, I am a curious and analytical person, so I try to understand why the Pivot works so well for lowering. The difference between a Pivot and other guide devices is pretty minor really, just a pivoting attachment point. But I don’t think the Pivot works better simply because it can pivot on the attachment point. Other guide devices can pivot on their attachment point too, so why don’t they work as well for lowering? One reason could be with the device weighed by a climber, there is a lot of friction between the attachment point of the device and the biner used to hang it from the anchor. But if that’s the only reason why other devices don’t work as well, then can’t you hang them with a DMM revolver biner and get the same smooth action as the Pivot? I intend to test this when I get a chance, but my guess is it’s not so simple. I think there’s another reason why the Pivot works, is that the pivoting point is lower than the attachment point (closer to the rope). This reduce the lever arm between the rope and the pivoting point, makes it easier to lift and control. I think this reduction of the lever arm is the primary reason why the Pivot works, not just because it can pivot on the attachment point.

The fact that the ring moves is what is unique.

https://vimeo.com/116828237

Ted Pinson wrote:

Yep, that's it precisely.  Traditional designs with a rigid autoblock hole don't allow for a gradual release, so the switch is sudden and abrupt.  This means that you need a backup (friction hitch) and a mechanical advantage (redirect), otherwise you can have rope sailing through the device, nasty rope burns, and an injured or dead second.  The Pivot eliminates all of these problems by using a flexible autoblock hole that allows the device to...well, pivot, gradually releasing the block.  It's genius.

Sorry for some minor thread drift, but I feel the need to point this out.  A redirect is not a mechanical advantage, you are simply redirecting the same force.  

I do, however, completely agree with you about how nice the Pivot is to lower with.  I unfortunately can't find much use for mine now as I find the GriGri much nicer for one rope and I rarely use halfs.

Finally got a copy of the latest Climbing...LSD article in there....

I don't recommend lowering your climber on LSD...that just sounds dangerous.

Ted Pinson wrote:

I don't recommend lowering your climber on LSD...that just sounds dangerous.

But if they're high on LSD, how else are you supposed to get them down?

Bill Lawry wrote:

About converting to another friction mode by pulling on the eyelet ...

I'll also highlight that we experienced a failure mode with technique D.0 - flip the device with redirected brake strand.  The person was very cautious and so tried to do it very slowly.

The failure occurred at a point after the "guide mode" was defeated but before the device flipped.  Within the slot of the ATC Guide, the brake strand slipped completely past the load strand under body weight with an audible "pop".  This was with an 8.9mm rope.

Edit to add: the locker on the bight of rope did not flip. Even so, the belay device was essentially defeated.

Below is a video of the failure with one strand (8.9mm) with technique D.0 - flip device into normal friction mode while loaded.  Hopefully it comes across.  Note that this is not a catastrophic failure.  It is just a failure that ups the ante for quickly lowering a second a long-ish distance.  

http://www.cs.unm.edu/~bill/stuff/guide_mode_fail.mov

For pulling the eyelet, a 7mm cord redirected from above, with a second person weighting that.  And the brake strand was redirected to a munter on the belay loop.  

It was really easy to get this to occur.  Allowing some tension on the redirected brake strand helps - but not an unrealistic amount. Some tension is prudent. Edit: or maybe any tension is no bueno.

I could not get this to occur with two strands and one person's weight split between the two strands.  But if I had two seconds with one weighting a strand and the other not, I think it reasonable that this would occur.   Soberingly, for a threesome, double 8.9mm are my go-to pair doubles.

Ted Pinson wrote:

I don't recommend lowering your climber on LSD...that just sounds dangerous.

Can you elaborate a bit more on why you think the LSD method is a "dangerous" lowering method? Also, how is this any more dangerous than your non-backed-up system using the DMM Pivot? Just would like to hear some clarification. 

Andy Hansen wrote:

Can you elaborate a bit more on why you think the LSD method is a "dangerous" lowering method? Also, how is this any more dangerous than your non-backed-up system using the DMM Pivot? Just would like to hear some clarification. 

Wow.  Dense much? ;)

https://en.m.wikipedia.org/wiki/Lysergic_acid_diethylamide

Ted Pinson wrote:

Wow.  Dense much? ;)

https://en.m.wikipedia.org/wiki/Lysergic_acid_diethylamide

Ah, my fault. Didn't see that it was tongue-in-cheek. 

Andy Hansen wrote:

Didn't see that it was tongue-in-cheek. 

Probably not a bad sign.  :-)

Ted Pinson wrote:

I don't recommend lowering your climber on LSD...that just sounds dangerous.

In the documentary Valley Uprising, there's a bit where some 70s climbers climbed big walls on LSD. I guess maybe they were so good at climbing they never needed to be lowered?

EDIT: This page says it was Jim Bridwell, although the reliability of that source is questionable since they spelled his name "Birdwell".