The Meat of SRT thread...whatsup?

[murphy4trees]

Well that brings up trhe question of ...
Do we really need the system to bear 5400 lbs when we're just ascending to set a TIP??? Many times the tree won't hold close to that. I suppose it's better to keep the 5400 at all times rather than start making this or that exception...
Which brings us back to steel auto locking biners... They should be close to the 5400 even in Nick's application... though no mfg is going to OK that use..
So its a personal decision.. are you OK with breaking the rules when you think its safe. I admire MMs attitude.. stick to the rules.. its good for your health... Nick wants spped and ease.. maybe he should be looking for other ways to achieve that end.. Maybe he's really safe and we're just overly cautious.. the problem is you only get one life to find out the answers..

I break the two tie in rule and one hand a chainsaw from time to time, but have greatly reduced those times after reading post from MM and others and looking over Tim Walsh's fatality report data... There are a lot of ways to die and a 10' fall has killed many an arborist....

 

[Tree Machine]

Well said TM, like the drunk who drives home wasted every day and has never crashed, it's gotta be safe.

Well said, Mike, like comparing a grape to a bowling ball.

You are looking for somebody to tell you that no matter how you side load a carabiner, it's strength will not be reduced to 5400 pounds. It ain't going to happen!

Mebbe we should ask a metallurgist.

So its a personal decision.. are you OK with breaking the rules when you think its safe.

I wouldn't put my life on it unless I knew it was safe. I value life as much as you, Mike.

 

[Kneejerk Bombas]

In your picture TM, you showed two inverted biners on a huge trunk. There is almost no sideloading. The strength reduction in this picture due to side loading is next to nothing.
Next, young Nick finds himself with a splice at the end of his rope and realizes that he can't easily attach it "running" midline. Even tying a knot is hard because of the splice, so he clips on a carabiner and pulls it up. It works so it must be OK.
Here's what he has:

 

[Tom Dunlap]

In TM's picture of the SRT anchor there are a couple of comments due.

When you use two biners in an opposite/opposing setup they should be the same biner. The symmetry is very important so that the load is shared equally.

Look at the wire gate biner. If the rope were to move it would go across the gate. NOT GOOD...

When the rope exits the o/o biners it should cross the major/back spine of the biner.

Both biners should be oriented so that the load is on the major/back spine.

I think that MM's pic is meant as a cartoon. If so, then having the rope exit across the gate spine makes sense. If the pic were of a real, working situation, the rope should cross the other way, with the gate pointed up.


Tom

 

[Gord]

Cartoon or not Mike's pic illustrates a situation where a biner should not be used. Even if the biner was orientated the correct way the gate of the biner is taking a lot of strain due to the small stem it is around. Those plastic gates are not very strong, especially the little tab that prevents it from opening. Triacts or grenade gates aren't much better for this; they are easily opened when pressed against a surface and moved under pressure.

As bradley pointed out, there is an illustration in the petzl work catalogue that shows a carabiner being used to choke off a line at the base of a tree. The trunk is of course of large radius and the setup could be easily inspected before loading, unlike a choked TIP in the top of a leafy canopy.

I think that the safest way to go is a running bowline. If you've got a spliced eye, leave a long tail, even safer. Added time is what, maybe a minute and a half.

 

[Kneejerk Bombas]

Originally posted by Tom Dunlap

I think that MM's pic is meant as a cartoon. If so, then having the rope exit across the gate spine makes sense. If the pic were of a real, working situation, the rope should cross the other way, with the gate pointed up.


Tom

It was meant to illustrate a bad case scenerio.
The question becomes, where do you draw the line between what some might call an acceptable set up and my cartoon?
My advice is to do things correctly, even if going against manufacturers recommnendations seems safe on this one occasion.
Petzl's idea of using a strap makes sense. Nick could still have his splice and carabiner, he'd just have to add a strap and put his rope's tail, or his whole rope bag, through the loop before he pulled it up.
That wouldn't take a minute and a half.

 

[NickfromWI]

Originally posted by murphy4trees
I'd be patient and accept their answer that it is an improper use for their gear, even though we all already knew that.

This is why I am so interested in this topic. We don't already KNOW that it is unsafe. All that can be said right now is that it seems unsafe. I want a solid answer, not a feeling.

Mike, your solution of adding the sling from the ground is about as efficient as just tying a running bowline. The reason why I liked the "Nick" method (I don't know if I want my name affiliated with this concept! who started this thread, anyways?).....anyway- the main reason I liked it is that I get up there, open the carabiner once, slip it onto my saddle, and I'm clipped in (after tying on my friction hitch). The running bowline is an easy solution, but requires the untying of a knot. That's the wasted time I am trying to avoid.

And yes, I realize that the time we are talking about here is but a minute, but there is something quite refreshing about getting done with a tree and knowing you've eliminated all unnecessary steps. That is what I am aiming for here.

What I want to know is, what are the limits. Mike, you posted this....

Originally posted by Mike Maas
In your picture TM (the one with the carabiners at the base of the tree), you showed two inverted biners on a huge trunk. There is almost no sideloading. The strength reduction in this picture due to side loading is next to nothing.
Next, young Nick finds himself with a splice at the end of his rope and realizes that he can't easily attach it "running" midline.

I can sum up one point in this post as follows: "Attaching a rope to the base of a tree using the Nick method is okay due to the large size of the tree. It is not acceptable at the top of the tree because the limb is small."

So this leads me to a question. Yes, you can use the nick method 2 feet above the ground. Can you do it 4 feet? Yes? Well how 'bout 8' off the ground? Yes.....and so on.

What are the limits? Right now we have one thread in which people are saying yes it's good (at the base of a tree) and no, it's not good. They both cannot be true. What if I am climbing a 100' tulip tree, but I throw my throwline to about 60' and it goes around a limb that is 18" across....is that okay? The answer right now is, "Maybe."

So how do we find the answers, Mike?

love
nick

 

[murphy4trees]

Ya that's it MAYBE...
MAYBE you get to plunge to your death today...
It almost happenned to a friend of mine today....
He was working single line at 75' when he felt his climbing line go limp... thought it had broken off a twig... only to realize that he had cut the standing end of the climbing line right through with the chainsaw..
NO second tie in = dead climber!!!!!!!!!!!
YES second tie in = shorter rope and everyone goes home for dinner... no funeral, no 3 kids growing up without a father... NO BRAINER..
This guy is a skilled and experienced climber.. he just made a mistake like the rest of us humans make all the time...
The rules are the rules to keep us from making the kind of mistakes that kill!!!

 

[Tree Machine]

I believe that's the question of the day.... How DO we find the answer to this? Speculation and conjecture aren't going to prove anything.

Mike, I respect your opinion that this is not the 'correct' way to do it, but it is just that - an opinion.

Backing your opinion by posting a pic of 1) an aluminum biner, 2) around a tiny branch that no one in his right mind should use as a TIP and 3) orienting the gate the wrong way doesn't show any 'proof', however, you get credit for showing us how it shouldn't be done. For this, I thank you. Hopefuly many have learned something in seeing that.

Tom, I acknowledge all your points as valid. I encourage everyone to re-read them. Yes, I sunk an aluminum hotwire in behind a 50 kN steel triple lock as a backup for my own peace of mind, not because it was necessary. Generally this is done with two non-lockers to insure against a potential gate failure, and yes, they should be identical.

Once the method 'a la Nick' is employed, the rope tensioned and the climber gives the rope the obligatory couple bounces before ascending, the set really doesn't have much chance to move. Also, the friction of the rope around the limb lessens the forces on the caribiner to somewhat less than what the climber actually exerts on the rope.

Objective testing would be difficult as actual forces would vary with limb diameter (degree of lateral force) and bark texture (friction). Also, in all fairness, the rig should be tested at actual forces that it would experience in a realistic work setting. Even if a steel autolocker, method 'a la Nick', were subjected to an excessive weight, say 10 times that of John Paul Sanborn, and it withstood 100 out of 100 tests, I still don't think MM would concede that method 'a la Nick' is 'safe'. That's OK. I'm not suggesting anyone adopt the method. But to invalidate it publicly, based on pure, hypothetical opinion is not OK.

 

[Kneejerk Bombas]

Originally posted by Tree Machine
Mike, I respect your opinion that this is not the 'correct' way to do it, but it is just that - an opinion.

An opinion shared by the manufacturer.

Sending a climber up a tree using a method specifically deemed incorrect by the manufacturer of the tool he's using, both in literature stapled to the tool when new, and backed up by personal communication with representitives of the manufacterer, is libelous, and stupid.

Originally posted by Tree Machine


But to invalidate it publicly, based on pure, hypothetical opinion is not OK.

So it is your opinion that a method is safe until proven unsafe???

This whole dialogue gets dumber and dumberer.

That in mind, let's go back to my drunk driving analogy, it safe to drive drunk, if I only drive very slowly and in my driveway, and I know it's not safe if I drive rush hour in the city drunk, so where do I draw the line?

 

[NickfromWI]

Mike, you say the manufacturer shares your opinion about the evilness of this method. All they've told me is, "we can't condone that." That does not mean they know it's bad. No, it's not safe until proven unsafe, but it's not unsafe until it's proven unsafe.

Limit yourself only to the things you now know and you will never learn.

love
nick

 

[Tom Dunlap]

How much would you trust your biner strength-wise hanging on it with the gate open?

Most biners have an open-gate rating on them. You'll be surprised how high that is compared to closed. If its not on the biner the homepage will have the specs.

Tom

 

[Kneejerk Bombas]

Originally posted by NickfromWI
Mike, you say the manufacturer shares your opinion about the evilness of this method. All they've told me is, "we can't condone that." That does not mean they know it's bad. No, it's not safe until proven unsafe, but it's not unsafe until it's proven unsafe.

Limit yourself only to the things you now know and you will never learn.

love
nick

Read the liturature that came with the biner, Nick.

And deliberately mis-quoting, I think he said "Unequivocally, I cannot recommend using this method." and "...you are improperly loading the carabiner"

Originally posted by Tom Dunlop
Most biners have an open-gate rating on them. You'll be surprised how high that is compared to closed. If its not on the biner the homepage will have the specs.

Still well below 5000 pounds, Tom. Are you condoning climbing on gear rated at less than 5000 lbs???

 

[RescueMan]

Originally posted by Tree Machine
I believe that's the question of the day.... How DO we find the answer to this? Speculation and conjecture aren't going to prove anything. Objective testing would be difficult as actual forces would vary

And this is the crux of the issue. There is no way to test this application because of the literally infinite number of variables. That's why every carabiner manufacturer warns against side-loading (and none will condone it).

There is no way to prove that it is safe. There is a simple say to prove that it is unsafe. The first time someone gets killed using it. Who wants to volunteer?

Aluminum carabiners typically are 1/3 as strong with the gate open. In fact, that's why they invented those strange wire-gate biners, to minimize the mass of the gate to prevent them from bouncing open while a rope is whipping through them. Many aluminum carabiners have broken when a rock-climber fell on them in a gate-open condition.

Would I use a carabiner as a choker? Yes, if it was a locking steel biner (about 65kN), it was on a relatively smooth large diameter pole, I could visually inspect it before applying a load, and I was reasonably certain that it's gate couldn't be rolled open. If I could not inspect it, then no.

And, TreeMachine, that wire-gate backup probably weakens your system. Because it is shorter, the wire-gate biner is taking all the load and, if it fails, then the steel biner would get shockloaded and perhaps rotate a bit making the gate vulnerable to becoming unlocked.

- Robert

 

[RescueMan]

This is a test

This is a test to see if I can post to this thread.