Excruciating 20 minute cat vid is actually about SRT? Seriously?

moss

moss

Been here much more than a while
Location
Carlisle, Massachusetts, U.S.
This is a niche corner of SRT access and work positioning in trees. My go-to for a lot of situations working and rescuing. I've been developing prototypes as many of you know for "integrated" canopy anchors. After enough hours and years on some of these systems they are seriously holding up practically as climbing technique, as well as solid life support gear and technique.

Choking alloy carabiners gate up is always weirding people out, it's understandable. Tree climbers have an equally superstitious and logical/safe work practices mentality. Subtlety is possible, we are not ignorant. There are "rules" that limit most of us in "industrial" tree climbing. and we're always "protecting" the newbie and "technically/culturally isolated" climbers from themselves to promote sound safety practices.

That said there's moving forward to be done. For those of us who want to and can do it smartly, lets do it.

This is short rope climbing to safely achieve a goal in a tree. An 85' line and a 15' line. Always backed up all the time. Choked alloy is for short length and/or non-remote setting anchors. Loading the carabiner spine dangerously for this scenario is illusory as shown in this vid, there is no shock loading in a practical sense. And no room for the spine to move. A quality alloy carabiner is not a crispy critter, it bends under extreme loading against more or less cylindrical objects. and does not bend under positional loading forces. Knee jerk reaction is a mistake to what you'll see. Gate up, gate up, gate up, opposing the direction of load. Can't say it enough. Wood diameter getting too small? Wraps. 2 wraps, 3 wraps, whatever it takes. We all know the friction power of wraps.

I know I just peppered you with light jaw punches, especially those surprising left hooks. Feel free to enjoy anyway, doesn't hurt that much from a climber who weighs nearly nothing ;-)


-AJ
 
Aerial Traveler said:
Enjoying the cat rescue SRT video.

Choking carabiners? What's next, climbing without a lanyard? Just joking, I use carabiners in non-remote-set cinch applications all the time. I did notice you have those custom slic pin shackles right there, ready to deploy for the cinch. Do you prefer the carabiners due to speed and convenience of opening? Asking for a friend...

As a culturally isolated recreational climber that definately weighs something, I find your videos to always be educational and rarely controversial. Let us progress forward and enjoy the cool shade of the grey area.
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Awesome. Yeah, slick pin shackle of whatever kind Quickie or my custom version is too slow when I’m advancing in a tree purposively as in work or rescue situations.

Thx for the backup and excellent hilarity!
-AJ
 
To clarify about the "slowness" of threaded shackles or slic pin shackles for advancing... there are sooo many things that will slow a climber down advancing when there is some focused goal in climbing, work always, and rescue work always. Behaving in a rushed way makes things worse, ruins subtle decision-making processes that keep a climber safe on a consistent basis. Yeah, sometimes you have to turn it on with quickness but it is dangerously unsustainable for a fundamental climbing approach.

That said, we're all shaving the little things that slow us down. It adds up. Removing as many efficiency obstacles as possible is bread and butter for climbers. Fidgeting with shackles and quick links is fine but save it for the right moments.
-AJ
 
TreeCo said:
The cat whisperer!

They don't behave like that for me.

Well done.
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I've had some doozies! Flying pee, poop, flying cat anchored to my fingers by its teeth, the expected. I try to handle them as little as possible these days. Sometimes you have to grab them, sometimes a battle ensues.

Then there's the ones that jump on your shoulder and give you a head butt.

Thx TreeCo!
 
I don't think you should be encouraging people to use a biner in a cinching anchor point like you're doing. Sure, go ahead and you do you, but you probably shouldn't be encouraging others to do the same. Using a piece of hardware in a configuration not recommended by the manufacturer is a good enough reason not to.
Why I believe this to be an issue comes down to cycles to failure and safety factor ratings. A biner is significantly weaker when being used like this (especially on a small diameter stem like what you have). Most of these biners have a side load breaking strength of 7kn. Now sure, conceptually you'll never generate that force in this configuration but think about cycles to failure with relation to safety factors.
Safety factors give the user a general rating to which hardware should not be pushed past in order to get the longest life span out of it. Everything breaks down eventually, and over time the piece can be more likely to fail at a lower breaking point. Safety factors for life support gear is 10:1 and if you apply this to that side load rating of 7kn (which is roughly 1573 lbs) you get a safe working limit of 157 lbs (not much at all). So basically because you can easily load that spine with that much (and more). This will over time significantly weaken that biner shortening it's life span.
This is just my opinion on why such configuration can be dangerous and I am happy to hear your thoughts on it. Sorry for the long rant
 
Sprucinator said:
I don't think you should be encouraging people to use a biner in a cinching anchor point like you're doing. Sure, go ahead and you do you, but you probably shouldn't be encouraging others to do the same. Using a piece of hardware in a configuration not recommended by the manufacturer is a good enough reason not to.
Why I believe this to be an issue comes down to cycles to failure and safety factor ratings. A biner is significantly weaker when being used like this (especially on a small diameter stem like what you have). Most of these biners have a side load breaking strength of 7kn. Now sure, conceptually you'll never generate that force in this configuration but think about cycles to failure with relation to safety factors.
Safety factors give the user a general rating to which hardware should not be pushed past in order to get the longest life span out of it. Everything breaks down eventually, and over time the piece can be more likely to fail at a lower breaking point. Safety factors for life support gear is 10:1 and if you apply this to that side load rating of 7kn (which is roughly 1573 lbs) you get a safe working limit of 157 lbs (not much at all). So basically because you can easily load that spine with that much (and more). This will over time significantly weaken that biner shortening it's life span.
This is just my opinion on why such configuration can be dangerous and I am happy to hear your thoughts on it. Sorry for the long rant
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I appreciate your concern! No regulatory guidelines/rules approve the use. I'm pushing experimental technique forward, I've successfully used this technique for ten years at least. There are very specific considerations like always "gate up" opposing the direction of load. Never use for a remote anchor installed from the ground for example. I believe this technique will become more accepted going forward. Petzl has moved in that direction by showing carabiner cinching for spar work with the ZigZag, it is shown in the safety literature that comes with the ZigZag.

My carabiners have a normal/long functional life. I've tested alloy carabiner spines by hammering them over (in a vise). The spine bends quite a bit before the gate pops then the alloy starts longitudal cracking, it takes a full 45 degree bend to break the spine. In tree climbing the spine of a cinched carabiner is not levered over a hard corner, if even the slightest deformation occurs the gate end will not align to the nose and will not function. In general if the gate is otherwise clean and functioning, it will not lock if the spine is deformed. This is an excellent regular inspection/test of a carabiner whether or not they are used for cinched anchors. To-date I've found zero spine deformation for any of my alloy carabiners.

To sum it up, in order for a carabiner spine to deform, there needs to be room for it to move. If it doesn't move, no deformation, no damage to the carabiner. Very subtle deformation is easily detected by inspecting/testing gate functionality. Every climber is responsible for their own safety.
-AJ
 
I remember back in the day I was told never post an image of a Blake's Hitch online. The reason being a beginner could learn to tie the hitch and potentially hurt or kill themselves climbing without proper supervision/instruction. I disagreed then and now on the concern that: "Someone might hurt themselves by doing what you do" (in this example using a Blake's Hitch). It is the same as when I showed my life support hand-stitching process in this forum. At least one person with significant influence in the tree climber community said "People will die because of what you've posted". A bunch of years later nobody has died who has created their own life support gear using that stitching technique. I'm an optimist, I have faith in the common sense of humans, especially our sense of self-preservation and survival. I'm not talking about desperate drug/alcohol etc compromised climbers, that's a whole 'nother problem.
-AJ
 
moss said:
I have faith in the common sense of humans, especially our sense of self-preservation and survival . . . . .
-AJ
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And these days there's also all manner of pull tests with tackle and strain gauges, commercial break testing services and maybe just good old fashioned 4Runner clevis "pull till you worry about the truck coming apart" pull testing too, to validate your splicing/ sewing method (recipe). At some point, esp for a lanyard, it's gotta be strong enough . . . esp if you keep breaking biners or the textile itself. Kinda where I stand now too.
 
DSMc said:
I enjoyed watching this when it first came out.


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Ha! That is pure gold, thx! And even a Kong, the gate still worked! I went through a few of those Kong pear-shaped biners early on, the gates always went to crap well before they should have. That's before I ever cinched a carabiner.

Test couldn't have been conducted by a better man, the choked biner conversation has been going on for a long time. It started with the basic warning on all carabiner safety literature, the graphic with red X or skull and crossbones shows a carabiner spine levered over a sharp rock edge for a rappelling top anchor. It translates into tree climbing as "Be aware of this!" but.... not what happens when a carabiner is choked on rounded profile wood. For positioning SRT anchors with my lanyard a simple choke is perfect. For life support quality on small diameter wood two or three wraps takes most of the load, the carabiner functions as a keeper, it is getting low load.

Key concept is, choked carabiner is not kosher for setting a remote canopy anchor. I always hand set any choked carabiner or at least at a short distance above me (when advancing) so I can control the carabiner orientation on the set and easily verify visually that the gate is in a safe and locked position.

Nuance doesn't translate well in industry guidelines so it's understandable that the practice is widely discouraged.
-AJ
 
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Yeah, test stopped at 13kn, they were pulling the tree over even though the line was redirected straight down for optimal load dynamics for the tree. Gate still functioned after 13kn meaning no spine deformation occurred. It probably flexed some barely measurable amount but recovered, the gate wouldn't work if any fixed deformation happened.

Giorgio never made a big deal about that test but it was significant at the time.
-AJ
 
ghostice said:
No cats, but cinching stuff galore - remember this thread from a while back AJ?
What happened to, was it Brocky's bent figure eight kinda piece of tree gear artwork? I really liked that idea . . . .
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I still use my integrated bow shackle anchor from time-to-time, more tools in the box or should I say "on the end of my lanyard". I'm thinking of going back to a ring for my next one, it's easier to pass the loop through it than the shackle when creating an anchor.

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-AJ
 
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I like the idea of a ring - for me, the simpler the better is a happy place to be, esp. for life support - (too many years of failure modes analysis engineering I guess).
On original topic of cats, I should also add that a domestic cat probably wouldn't last eight days in a tree in these parts (see one of Augusts latest couple AdTube videos) - here a cat named Bob would probably help 'em down long before that amount of time passed. We have Bobcats everywhere it seems last few years (and rabbits too) . . . . All the squirrels look nervously over their shoulders all the time too. :-) Cheers AJ.
 
ghostice said:
I like the idea of a ring - for me, the simpler the better is a happy place to be, esp. for life support - (too many years of failure modes analysis engineering I guess).
On original topic of cats, I should also add that a domestic cat probably wouldn't last eight days in a tree in these parts (see one of Augusts latest couple AdTube videos) - here a cat named Bob would probably help 'em down long before that amount of time passed. We have Bobcats everywhere it seems last few years (and rabbits too) . . . . All the squirrels look nervously over their shoulders all the time too. :) Cheers AJ.
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Thx! The stainless shackle is not a cheap knock-off and is brutally strong. Ring is good too. A steel ring might be even better for the throwing weight.

I’ll check out August’s latest, thx. I had a cat up close to 4 weeks during strong heat, what saved him was 3 days of rain in the middle of that. Rabbits are bobcat fuel for sure, more rabbits = more bobcats ;-)
-AJ
 
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