Login with Facebook
 ADVANCED
Why shouldn't you clip a bent gate carabiner into the protection or bolt?
View Latest Posts in This Forum or All Forums
   Page 1 of 1.  
Follow replies to this topic? Notify me at the top of web site.
1

Email me.
 
 
By Burk S.
From Lebanon, Oregon
Jul 31, 2012
REI wrote this warning and I am wondering what it prevents:

Warning: Bent-gate carabiners should only be used on the end of the quickdraw or runner which the rope clips into. Never clip them directly to the protection.

Any thoughts?

FLAG
By redlude97
Jul 31, 2012
It's easier for the hanger to open a bent gate as it rotates around

FLAG
By Buff Johnson
Jul 31, 2012
smiley face
Both bd & petzl show the potential for it to fatigue due to how constricted it becomes in the sling. So it's more the sling & constrictor band (or whatever you use) meant for better clipping rope-side which won't allow for the biner to move with the energy. Essentially, it's somewhat similar to crossloading a biner.

FLAG
By Rob Warden, Space Lizard
From Springdale Ut
Aug 1, 2012
blah
What if the string or gasket is off? Its really that much more likely to open?

FLAG
By socorroscott
From socorro, nm
Aug 1, 2012
The bent gate carabiner is designed for ease of clipping the rope, and the constricted end of the draw allows that carabiner to stay in place for clipping the rope. Also, the constricted end of the draw prevents the carabiner from cross loading as rope drag moves the draw around. The straight gate end of the draw for attaching to the anchor is loosely connected to the carabiner which allows the draw to move with the rope drag, thus preventing twisting and cross loading.
With a bit of sport chuffing, the anchor end of the draw will get little nicks and burrs on the carabiner. This is no big deal in itself, but potentially dangerous to run the rope through the roughed up carabiner. I am not sure if the bent gate is easier to unclip from a hanger or not, but they have the same strength rating as a corresponding straight gate. Sorry if that was a bit long winded, but I hope it helps.

FLAG
By 20 kN
From Hawaii
Aug 1, 2012
Buff Johnson wrote:
Both bd & petzl show the potential for it to fatigue due to how constricted it becomes in the sling. So it's more the sling & constrictor band (or whatever you use) meant for better clipping rope-side which won't allow for the biner to move with the energy. Essentially, it's somewhat similar to crossloading a biner.



There are two reasons why you should not clip the bent gate side biner to the hanger.

The first is if you clip the rope side biner to a hanger, fall on it, and then clip it to the rope on a different climb, you can shred your rope. When you take a fall on a steel hanger, the hanger cuts into the aluminum biner and leaves a sharp indent called a hanger scar. Biners with hanger scars should not be clipped to a rope.

Second, the rope end biner of a draw is almost always fixed to the dogbone someway to enable easy clipping. It is not recommended, but not a death sentence, to clip the fixed end of a draw to the bolt. The reason being is that if you clip the rope end to the hanger, rope drag can flip the biner around causing it to come unclipped from the hanger. That is the reason why manufacturers do not fix the rope end of the biner to the dogbone. But in reality, it is hard for this to happen. I used to climb with fixed biners on both sides of my draws before I learned about this issue and unfixed the bolt side. For two years I climbed that way and never had a biner come unclipped. However, you do increase the risk of it coming unclipped if you use a fixed biner on the bolt side, so it is not recommended.

Lastly, there is nothing inherently unsafe about using a bent gate biner on a bolt. The issue is using the rope side biner on the bolt. But, if for some reason you want to use bent gates on both sides of your draw, you could. Just dont mix them up, use one for the bolt side and the other for the rope side.

edit: It is also more likely for a biner that is terminated short to the draw to get crossloaded and pinched in a hanger.

FLAG
By berl
From Oregon
Aug 2, 2012
I also like this part from the original REI page :

" But if not used properly, bent-gate carabiners can unclip from your rope. "


right, unlike other carabiners? Does anyone have any solid information about bentgate carabiners being more likely to unclip due to back clipping or being more susceptible to unclipping from a hanger? Controlled comparisons of otherwise identical, straight vs bent gate only, please. Anecdotes need not reply.

FLAG
By Buff Johnson
Aug 2, 2012
smiley face
Petzl's tech pdf on their draw shows the fatigue issue, page 4 diagram (they even drew a double-sided arrow to show the crossload). That's the reason for the safety notice. I tried to see if I could just cut & paste the diagram, but I can't.

They have the other issues diagrammed as well.

FLAG
 
By 20 kN
From Hawaii
Aug 2, 2012
berl wrote:
I also like this part from the original REI page : " But if not used properly, bent-gate carabiners can unclip from your rope. " right, unlike other carabiners? Does anyone have any solid information about bentgate carabiners being more likely to unclip due to back clipping or being more susceptible to unclipping from a hanger? Controlled comparisons of otherwise identical, straight vs bent gate only, please. Anecdotes need not reply.

Indeed, a backclipped draw that has a bent gate on the rope side is more likely to come unclipped than a backclipped draw with a straight gate on the rope side. The reason being is that it is easier for a rope to catch a bent gate than a straight gate. After all, that is specifically what bent gates are designed for. They are designed to catch the rope making it easier to clip the draw. However, the relevancy ends there. Bent gates do not have any influence on the chances of the draw coming unclipped from the bolt.

As far as scientific controlled tests go, sorry, I dont have much to provide as I am fairly confident the test you are asking for has never been conducted. Or at least, it has never been publicized. Unclipping a backclipped draw is actually pretty difficult in the real world. I have tried really hard to get a backclipped draw to come unclipped before, and I couldent do it. I gave the draw the best possible chance: I used a really short draw, I fixed the biners on both ends of the dogbone and I used a solid bent gate on the rope side.

FLAG
By 20 kN
From Hawaii
Aug 2, 2012
Buff Johnson wrote:
Petzl's tech pdf on their draw shows the fatigue issue, page 4 diagram (they even drew a double-sided arrow to show the crossload). That's the reason for the safety notice. I tried to see if I could just cut & paste the diagram, but I can't. They have the other issues diagrammed as well.

Do you have a link?

FLAG
By Buff Johnson
Aug 2, 2012
smiley face
their website is a friggin pita. try this (as an example):

petzl.com/us/outdoor/non-locki...

click on the tech notice link for the pdf.

FLAG
By kBobby
From Spokane, WA
Aug 2, 2012
Linky

FLAG
By Greg D
From Here
Aug 2, 2012
Out of the blue.  Photo by Mike W. <br />
Linky no work!

FLAG
By 20 kN
From Hawaii
Aug 2, 2012
Buff Johnson wrote:
their website is a friggin pita. try this (as an example): petzl.com/us/outdoor/non-locki... click on the tech notice link for the pdf.

Yes, indeed the issue they show in the tech notice is made more likely if you clip the fixed end of the draw into the hanger. But, that issue can happen on the free end of the biner as well, it's just not as likely. But in any case, the chances of that happening are pretty slim, regardless if you clip the fixed end to the hanger or not. Furthermore, the UIAA closed gate strength requirement of 20 kN is sufficient to allow you to load the biner halfway between the gate and the spine, as shown in the example, and not break the biner on a single pitch fall (assuming the gate stays closed). I have pull tested a few biners with the load placed in the middle as shown in the diagram, and in all instances, the biner was still stronger loaded in that manner than it would have been if loaded correctly with the gate open. In other words, the biners were still strong enough to arrest a single pitch lead fall. However, I have never tested the biner's strength with the load placed right next to the gate. I am curious how much that would reduce the strength.

FLAG
By kBobby
From Spokane, WA
Aug 2, 2012
Now it does.

FLAG
By Buff Johnson
Aug 2, 2012
smiley face
20 kN wrote:
Furthermore, the UIAA closed gate strength requirement of 20 kN is sufficient to allow you to load the biner halfway between the gate and the spine, as shown in the example, and not break the biner on a single pitch fall (assuming the gate stays closed).


Which is why I said it's a fatigue issue.

FLAG
 
By 20 kN
From Hawaii
Aug 2, 2012
Buff Johnson wrote:
Which is why I said it's a fatigue issue.

What do you mean by fatigue? As I understand it, the term fatigue, in material sciences, refers to the eventual failure of a material from cyclic or long term excessive loading. I don't see how either of those apply in this example.

FLAG
By Michael Roadie
Aug 2, 2012
Sugarite
I have bent gate positrons for the protection side and hot wires for rope side with petzl dog bones inbetween. Am I gonna die? If I understand what Petzl is saying correctly, it has nothing to do with the biner, it has to do with the anchor-end of the dog bone, it "must be mobile (no STRING)". "STRING" meaning the captured end. WTF is rei sayin? It doesn't make sense to me that a bent gate should "Never clip them directly to the protection".

FLAG
By MattThomas
From Durham, NC
Aug 2, 2012
Me on the summit of Little Bear Peak after soloing the NW face.
socorroscott wrote:
The bent gate carabiner is designed for ease of clipping the rope, and the constricted end of the draw allows that carabiner to stay in place for clipping the rope. Also, the constricted end of the draw prevents the carabiner from cross loading as rope drag moves the draw around. The straight gate end of the draw for attaching to the anchor is loosely connected to the carabiner which allows the draw to move with the rope drag, thus preventing twisting and cross loading. With a bit of sport chuffing, the anchor end of the draw will get little nicks and burrs on the carabiner. This is no big deal in itself, but potentially dangerous to run the rope through the roughed up carabiner. I am not sure if the bent gate is easier to unclip from a hanger or not, but they have the same strength rating as a corresponding straight gate. Sorry if that was a bit long winded, but I hope it helps.


This video demonstrates what you're saying: even a small amount of wear on the 'biner can have extreme negative effects for the rope.


dmmclimbing.com/knowledge/cara...

FLAG
By Morgan Patterson
Administrator
Aug 2, 2012
Stoked...
MattThomas wrote:
This video demonstrates what you're saying: even a small amount of wear on the 'biner can have extreme negative effects for the rope. dmmclimbing.com/knowledge/cara...


wow... great demo.

FLAG
By wankel7
From Indiana
Aug 2, 2012
MattThomas wrote:
This video demonstrates what you're saying: even a small amount of wear on the 'biner can have extreme negative effects for the rope. dmmclimbing.com/knowledge/cara...


Interesting video for sure ! I thought most pre-made quick draws had the dog bone be stiff on one end ( Rope side) and loose on the other (Hanger side)?

I wonder if the metal wire of a nut could cause burs to form on biners?

FLAG
By J tot
From Tempe, AZ
Aug 3, 2012
zen
Buff Johnson wrote:
Which is why I said it's a fatigue issue.


Yea. Fatigue refers to slow failure due to cyclic loading. Like 100,000 to 1,000,000 times loading and unloading. I doubt anyone in the world has ever fallen on a draw a hundred thousand times.

So, what DO you mean?

FLAG
By Buff Johnson
Aug 3, 2012
smiley face
In certain respects, fatigue is typically discussed in a high number of low stress cycles. I don't disagree with the two posts offered about the high frequency, that is typical situation when loading equipment as intended.

However, fatigue is more abstract and need only to have cycles of stress which will have a cumulative effect to the point of failure. The failure will be influenced the shape, design, and where stress is placed -- a localized concentration of stress.

So I would offer that thinking in terms of #000,000 cycles may be short-sighted. In this case, there is a clear indication of higher stress by design & shape that places a fatigue problem concentrating where Petzl has indicated. I also appreciate the nicking and otherwise scuffing of the bent gate biner, which will lend a problem to the rope in the friction coef, and as well, will also promote a place for fatigue.

FLAG
By 20 kN
From Hawaii
Aug 3, 2012
Buff Johnson wrote:
In this case, there is a clear indication of higher stress by design & shape that places a fatigue problem concentrating where Petzl has indicated.

I dont see it as a fatigue issue. First off, it is extremely difficult to load a biner in the manner shown in the Petzl diagram in the real world. Even if you clip the rope end of the biner into the draw, you could fall on a draw 500 times and possibly never replicate the scenario shown in the diagram. Second, for fatigue to even start to play an effect, there has to be countless cycle loads. So when you take into account the improbability of the biner being loaded in the manner shown in the diagram with the number of times needed to cycle load the biner to failure by fatigue means, you come up with an impossibly high number of required lead falls. I would imagine you would completely wear through the bottom biner of the draw before you could take enough lead falls for this to be an issue.

FLAG
 
By J tot
From Tempe, AZ
Aug 6, 2012
zen
Buff Johnson wrote:
In certain respects, fatigue is typically discussed in a high number of low stress cycles. I don't disagree with the two posts offered about the high frequency, that is typical situation when loading equipment as intended. However, fatigue is more abstract and need only to have cycles of stress which will have a cumulative effect to the point of failure. The failure will be influenced the shape, design, and where stress is placed -- a localized concentration of stress. So I would offer that thinking in terms of #000,000 cycles may be short-sighted. In this case, there is a clear indication of higher stress by design & shape that places a fatigue problem concentrating where Petzl has indicated. I also appreciate the nicking and otherwise scuffing of the bent gate biner, which will lend a problem to the rope in the friction coef, and as well, will also promote a place for fatigue.


Still not fatigue.

FLAG
By generationfourth
From Irvine, CA
Aug 6, 2012
this is why I gave up using my sport biners for trad... no matter how many times I tell my partners to use the bent gates for the rope end they never pay attn and when I'm seconding half of the time the rope is clipped through the bolt end. I finally just ponied up for wiregates specifically for my alpine draws now. You don't fall that much on bolts on trad so your biners don't get as nicked/damaged as your sport draws.

Also, now I know why manufacturers don't fix the draw on the bolt end. Learn something new every day.

FLAG


Follow replies to this topic? Notify me at the top of web site.
1

Email me.
Page 1 of 1.