ACP- Carabiners

I've been involved with the Z133 committee for years but this is much later than when the biner trend started. The definition of what an autolock is came from another ANSI standard. A very good job of wordsmithing.

I have no clue exactly what the history is for not allowing screw gates. It seems to me, from using Stubai steel biners years ago, that they are more likely to jiggle open than autolockers. There has to be some testing out there by now. Every once in a while a piece of literature comes to light about some testing. Most of the testing seems to come out of Europe and is related to either sport climbing of some sort or rope access work.

Even though we're discussing this in a rec tree climbing forum the points are still valid. I have a [bad] gut feeling that a rec tree climbing guide/instructor would have a hard time defending the use of screw gates if it was shown that the opening of one lead to an accident. Even though there is no obligation for rec tree climbing to follow the Z it seems prudent to come as close as possible to the standard practices. Is there another field, rec or pro, that sanctions the use of screwgates for liffe support. I know that most all rock climbers use non-lockers for protection. That's a whole different situation and rope use style.

I would hate to hear about an accident that could have been prevented by using autolockers.

Originally posted by Tom Dunlap
I've been involved with the Z133 committee for years but this is much later than when the biner trend started. The definition of what an autolock is came from another ANSI standard. A very good job of wordsmithing.

Then I want to express my sincere gratitude for the work you and your team(s) did to help make tree climbing, esp. work related, safer.

Originally posted by Tom DunlapI have no clue exactly what the history is for not allowing screw gates. It seems to me, from using Stubai steel biners years ago, that they are more likely to jiggle open than autolockers. There has to be some testing out there by now. Every once in a while a piece of literature comes to light about some testing. Most of the testing seems to come out of Europe and is related to either sport climbing of some sort or rope access work.

I think you've nailed exactly what's troubling me - "...There has to be some testing out there by now..." One would think so. But since I can't find any reference to any testing done with screw locks in regard to tree climbing, it just imcreases my curiosity as to how screw locks got such a bad reputation.

What I fear is that there really hasn't been any testing, and hence ANSI standards were not based on test results and were based on word-of-mouth. While I respect the opinions of experts and professionals, without at least some competent testing they are simply isolated events and they could be simply due to lack of training or human error. The real problem is these things get passed on and on and changed slightly each time it is re-told.

Originally posted by Tom DunlapEven though we're discussing this in a rec tree climbing forum the points are still valid. I have a [bad] gut feeling that a rec tree climbing guide/instructor would have a hard time defending the use of screw gates if it was shown that the opening of one lead to an accident.

I agree! In fact, even though my climbing will be rec climbing, I still have a desire to follow the ANSI standards. Where the conflict comes for me, personally, when I first got into climbing, I bought and auto-lock and a screw lock and started devising tests to see if one had any significant advantages over the other, and to be perfectly open, I was pulling for the auto-locks all the way. One day I was sitting in my easy chair with my biners and a piece of rope just playing, tying knots, etc. and I put a half turn around a auto-locker, pulled it and it readily openned and released the rope! I was stunned. I did it over and over thinking I was missing something. I mean all kinds of people use this biner, surely it really isn't this easily defeated. So I thought, I wonder if a screw-lock will do that. I tried numerous times and couldn't make it do it. So I decided right then and there that auto-lockers are dangerous and I'm using only screw-locks.

Then I read the ANSI standard and was shocked to see that screw lockers were not approved. Thanks to this board I learned about double locking, auto-lockers. So I bought three of them. But again, I can open them almost as easily as I could my original auto-locker.

So there's the conflict for me. My simple tests disclosed to me that screw locks were the more reliable, yet now I learn screw locks have a bad rep and nobody has any hard evidence as to why they do.

Originally posted by Tom DunlapI would hate to hear about an accident that could have been prevented by using autolockers.

Again, I certainly agree with that sentiment, but also again why do you have the impression that the screw-locks are more likely to cause an accident than an auto-lock?

I'm just asking, I'm bewildered by all this. I want to be safe, in fact as safe as possible, but my personal testing reveals just the opposite of what the common thought is.

Way back, teachers were considered infallible. They used logic to project knowledge. For example, they deduced that because people had 32 teeth, horses also had 32 teeth. They were so confident of their logic that they didn't even bother to count the teeth in a horses mouth and taught it the way their common logic dictated. One day a student had the nerve to actuall count the teeth in the horses mouth - guess what he found? A horse doesn't have 32 teeth like he had been taught. When he reported this to his teachers, he was severely reprimanded and punished.

I'm not saying that's where we are by any means, but it does illustrate how things can get propogated without sound basis.

Any thoughts?

Here's my reductionist analysis of the screwgate versus autolocker question.

First:
Many tree climbers use screwgates. They are not intrinsically unsafe.

Second:
While you may be able to get a piece of cord to open an autolocker in the "lab", the collective experience of tree climbers is that well designed autolockers have not opened and caused a climber to fall. If anyone has heard of such a reported incident let's hear about it. It's worth noting that having the gate open will not guarantee that you will fall. Especially if your rope attachment is cinched on the biner.

Third:
I'm guessing, only guessing that the reason screw gates are not recommended is because of the opportunity for operator error, that is, forgetting to manually lock the gate.

In conclusion, I would weigh everything you've heard, climb low and slow, try your screwgates and make your decision. Ultimately we are all guided by our own judgement and responsible for our own decisions Every piece of gear has a potential loophole. As a new climber you have to either rely on your own gradual process of building trust in your gear and technique or rely on the experience of a teacher or mentor to help you make those choices.
-moss

Originally posted by moss
...
Third:
I'm guessing, only guessing that the reason screw gates are not recommended is because of the opportunity for operator error, that is, forgetting to manually lock the gate.
-moss

That's certainly one of the strong points for auto-lockers. I've forgot to lock one once myself. And that may be the best reason to use auto-lockers.

Ron,

Why don't you take this opportunity to solicit some feedback comparing biner closing mechanism tests on http://www.treebuzz.com/ and see what you find out.

not once in 15+ years of rope use in a variety of fields have i ever had a screwgate carabiner come undone. I can understand that NOT EVERYONE will check their biners before during or whenever on a treeclimb, but i have 100% confidence in a screwgate for treeclimbing. Work is another issue, i will use rope snaps because i have to.

I have hade ropes end up in sich a way around a double locker biner, that the outer part of the gate has slid down, and the gate was susceptible to being pushed open by rock, limb or another rope (under tension). That being said, I agree that a double action locker biner should be used by those entering the treeclimbing realm (treeworld), and that screwlinks (i'm talking Maillione Rapides ONLY, not screwgate biners) should only be used by experienced on rope persons, who check and recheck their gear frequently before , during and after a climb. Too easy for someone with little or some experience to forget to check a screwgate Biner.

I happen to love the Maillione Rapides, the large 16mm pear is one of my favorite (and cheap $$$) rigging items. I can get the large pear for 12 bucks, it solves many rigging problems for me , by allowing webbing slings to be spread out and not contact each other.

one thing that does bug me is a lot of people are under the impression that if someone uses anything other than a double locking biner, they are putting their life at risk, and that the screwgate or Maillione rapide will somehow fail up the aire, and the on rope use will fall. I'm dealing with now at work. They are used to double locks only, and have this weird fear of anything different.

As a facilitator taking clients into the trees, I only set them up with a Triple-Action Carabiner, AND I am the only one that gets to put it on or off the climber.

The Triple-Action seems to confuse more newbies and that is a good thing. I don't want them to touch it for fear that they may unlock it.

My 2 cents

Geof

I set my kids and adults up with delta screw links. I put the rope directly into the screwlink. It keeps the Blake's hitch lower for short arms of kids. My fingers hurt a bit from screwing them on and off however at the end of a 30 plus climber day (facilitated climbs). I use New Tribe saddles so the delta is already there.

I often wonder why the screw locking carabiner is frowned upon by tree climbers (rec and cutters), yet the screw link is accepted by most.

I would prefer my newtribe harness not have a screwlink...and that is just how the next one will be made!

Peter, I keep a gerber multitool with some quick access pliers on my saddle at all times. I bet they would see a lot of use on a day like you are explaining!

love
nick

nickfromwi wrote:

I often wonder why the screw locking carabiner is frowned upon by tree climbers (rec and cutters), yet the screw link is accepted by most.

A screw link has a finer thread, is threaded on both \"ends\" of the link, and takes many more turns to engage and disengage. Even if the screw/nut is turned enough to disengage from the end of the link, the rope or biner securing the climber still can't squeeze through, there is no gate to open wide. The link is strong enough to hold the climber's weight even if the link is disengaged. My experience from using them is that they not likely to unscrew far enough from tree or rope contact to allow the climber to come out of it.

nickfromwi wrote:

I would prefer my newtribe harness not have a screw link...and that is just how the next one will be made!

What would you replace it with?
-moss

PS: Weird how the underline dash keeps showing up like so: screw link

My intention is to replace it with the right rigging plate, or simply with a steel ring.

love
nick

I've done a lot of deliberating about where to use a rated (24Kn) screwgate, aluminum carabiner, in a climbing system. I've used it combination with both Weaver and New Tribe endless loop slings, in basket configuration, to redirect my primary climbing rope. Of course, it proved to be adequate to safeguard against a swing into the tree trunk, when I tested, low and slow. Also, I \"gate check\" after installing the sling and screwgate in the tree to be certain that all components are configured correctly, including that the screwgate is \"extra hand-snugged\" and the carabiner truly locked. Question #1: Is the redirect gear system I described above \"below standards\"? Question #2: Would a screwgate carabiner be suitable to build up the false crotch, as pictured on p. 63 of \"The Tree Climbert's Companion, by J. Jepson, 2nd Ed., instead of the double-locking carabiner, pictured and documented there? Question #3: Has there been a study of, probably non-metallic, add-on components that would serve to make a strength-rated screwgate carabiner vibration-proof and reasonably un-thread-proof?

Screwgate is below standards for a production/work climber but there are no rules for rec climbers. Many rec climbers use screwgates. I would be consistent in what ever gate technology I used for life support use and a redirect is life support. So if you use a screwgate to anchor your rope on your harness then use it for your redirects. If you use autolockers on your harness and lanyards do the same for redirects. Otherwise you're setting yourself up for a mistake when you're tired, stressed or lacking concentration. Be consistent, don't make your brain do flip flops around life support connections.

The way I see it, if you're trying to figure out a way to make screwgates more secure then you probably shouldn't be climbing on them.
-moss

Question #1: Is the redirect gear system I described above \"below standards\"?

Answer; There are not Written Standards for Rec Climbers. It is up to the Climber Desires and Responsabilty to be safe while climbing.

[/quote]Question #2: Would a screwgate carabiner be suitable to build up the false crotch, as pictured on p. 63 of \"The Tree Climbert's Companion, by J. Jepson, 2nd Ed., instead of the double-locking carabiner, pictured and documented there? [/quote]

I use both types of Biners (Auto-Locker and Screwgates) on my climbing system and I consider it to be safe and appropriate for my taste.

[/quote] Question #3: Has there been a study of, probably nonmetallic, add-on components that would serve to make a strength-rated screwgate carabiner vibration-proof and reasonably un-thread-proof?[/quote]

Answer: No,that I'm aware but I don't have all the answers anyway! (Vibration Proof? Never heard that properly closed Biners will open up if vibrated.)

moss and oldtimer: Many thanks. Great recommendations! Let's see: Be consist, i.e. \"no flip flops in trees\" (good tree-climber wardrobe decision, too?); tailor your climbing style to accommodate when you're tired; commit to safety and be responsible for maintaining safe habits and systems. Please correct me if I've misinterpreted either of you.

Having said all that, I believe that climb-rated (23kN+) screwgate carabiners, double-auto-locking carabiners, and stainless \"screwlinks\" are secure.

I believe that still unanswered question is, \"Can a screwgate carabiner be \"properly closed\" to adequately prevent un-threading and inadvertent opening?\". No, say the pros.

Vibration, friction, shock. I believe all these types of forces should be considered as potential methods for thwarting a gate lock.

I think that something like the Tory Red Cap Finger Tips (http://www.toryinc.com/) might be adapted to reduce the tendency for the screwgate lock to un-thread. In fact, I'd say there might be a size that would be adequate to similarly reduce the ease with which some have said that they can thwart the double-auto-lock gate. I'll probably buy a handful, strictly for the ground-based laboratory environment, and see what they'll do. OK, here's the disclaimer: This mere speculation on usefulness of a specific technology is in no way a recommendation to any climber to use any product referenced.

Thanks again.