Scheister TR and broken biner report

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Zoo

climber
Fremont, CA
Topic Author's Original Post - Oct 2, 2008 - 03:41pm PT
The Setup
Last Saturday, October 27th, my partner, Dave and I climbed Scheister on Sugarloaf near Lake Tahoe, CA. I had done this route almost exactly a year ago with Zander. The climb was going great until the alternative, stem finish which I had done twice before. From a large, fairly flat belay station, I climbed on top of some big blocks and clipped a bolt, which basically sits a foot or so above the edge of a wall that turns from vertical to fairly flat (maybe 20 or 30 degree slope). I used a 24” quickdraw with Mammut Moses carabiners on both sides and clipped the rope into the bottom biner. The bottom biner hangs over the edge by a few inches. From the blocks, I stemmed between two walls (pretty wide stem) and moved up until I could get my right foot high into a dish a little below and to the right of the bolt. I finished the move and then started to partially down climb the move to show Dave where to place his feet. I felt very secure with my hand on a knob and my right foot in the dish, but as I put my left foot against the back wall, I slipped.

The Event
My best guess is that it should have been a 3 or 4 foot fall on about 15 feet of rope. Before the fall, I was talking to Dave about foot position so he had me locked off and he was belaying me off of his harness, not directly off of the anchor. When the rope came taut, the carabiner attached to the bolt immediately broke in half. I dropped the rest of the way onto the slab near Dave. I landed on my feet and then slipped onto my rear. I came out of it relatively unharmed. I banged my wrist a little and had a cut that bled lightly to moderately and I bruised my butt and tailbone. A little shaken, we finished the climb via the 5.6 tunnel-through and walked off. Other than coming within one step of getting bit by a rattle snake, the walk out and drive home were uneventful.

The aftermath (so far)
I sent an email to customer support at Mammut and received a prompt response from their Hardware Product Manager. He expressed his concern and called for a UPS tag to pick up the broken carabiner so it could be shipped to Switzerland for testing. It is currently en route and we will have an answer when they have completed their testing. I will update as soon as I hear from them.

There are 10s of thousands of Mammut Moses carabiners out there. Please tell me there are a lot of people out there who have taken falls on these biners without them breaking. That would give me some measure of confidence. Anyone have a story?

Climb safe.

Cheers,

Mike Z





Strider

Trad climber
one of god's mountain temples....
Oct 2, 2008 - 03:44pm PT
Wow. Glad to hear about the safe outcome. Interested to hear the report on the biner as well...

-n
Ksolem

Trad climber
Monrovia, California
Oct 2, 2008 - 04:23pm PT
Send the biner to Mammut for inspection. They are a reputable company.

That said, I took one look at those biners, and bought something else instead. Just a gut feeling. No science or testing behind it.

I love their ropes and use them almost exclusively, so I do not mean to diss the mammut.

Good news you got off more or less unscathed. Cheers for that!

edit: ok, I am a slow reader.... we'll be interested in the results.
Gene

climber
Oct 2, 2008 - 04:26pm PT
Scary!
hoipolloi

climber
A friends backyard with the neighbors wifi
Oct 2, 2008 - 04:29pm PT
A friend of mine broke the exact same carabiner not too long ago. Maybe 9 months.

He had protected in the back of a chimeny and when he fell the biner hit the edge of the chimeny (it was on a long sling) and the thing just snapped in half, exactly how yours did. I might have the photos around here somewhere.. Ill take a look.

Glad your ok


edit:

I cant get the image to come through. But it looks almost exactly like your broken carabiner. His broke with a tiny bit less of the corner on it. The back post doesnt hook at all.
Zoo

climber
Fremont, CA
Topic Author's Reply - Oct 2, 2008 - 04:59pm PT
I'm sure that Mammut would be very interested in seeing that. Does he still have it? If not, maybe you can read the lot number from your pictures. On the spine, just before the ratings (23 kN closed, 8 kN open, etc) there should be a 4 digit number. The one of mine that broke was lot number 0107.

Mike
Zoo

climber
Fremont, CA
Topic Author's Reply - Oct 2, 2008 - 10:31pm PT

Mike
dwm

climber
Oct 3, 2008 - 06:31am PT


Mike with the broken biner after finishing the route.
He probably fell 12 to 15 feet right onto the granite slab below me.




    Dave
tom woods

Gym climber
Bishop, CA
Oct 3, 2008 - 07:53am PT
I've heard of biners breaking if they get knocked open during a fall. This biner was through a bolt? Yikes!

Tom
dirtineye

Trad climber
the south
Oct 3, 2008 - 08:27am PT
That sure looks like an open gate deal, but really in such a short fall, even open gate, those things are supposed to be good for from 7 to 9 kN.

I don't know which it is for those particular biners though.


You could roughly calculate the kN you generated with your mass in Kg and the distance fallen (up to the break) in meters. Supply your weight in pounds and the distance in feet and several people here could just convert and do it for you.

In your estimation, was it even possible for the gate to slap the wall and open in the fall?

The other thing is, could the biner have rotated up and gotten some weird torque from the hanger? This sound really unlikely since you had it on a two footer, but ya gotta wonder.

A break with the gate closed in your circumstances, barring a weird torque from the hanger would be REALLY scary.
xtrmecat

Trad climber
Kalispell, Montanagonia
Oct 3, 2008 - 08:42am PT
Mike, not to worry. I own a couple dozen of these and I know for fact that I've fallen on one for three consecutive tries on a move. I am not a dainty sport rat either see pic. 260 lbs.



I fell many more times this year and they most ceartainly were in the system then also. Most of my "Aid Only" pieces are racked on them and because I solo almost exclusively I don't use a lot of slings so they get pulled on a lot and hard. Rest easy, they are good beiners, but there are tougher.
If my fat butt won't weasel one apart they can hold some pretty good heft, however with a little twist or levering anyone's beaner will open like butter.
Bob
paganmonkeyboy

climber
mars...it's near nevada...
Oct 3, 2008 - 08:55am PT
"A friend of mine broke the exact same carabiner not too long ago."

did he send it in to mammut ?
ec

climber
ca
Oct 3, 2008 - 09:18am PT
'Glad you're O.K.

Punishment for hanging is usually more serious...

As noted above, with where the break is it appears that the gate was not totally shut. 'Better hope that's the case...

 ec

edit: the wire gate 'biners that do not have a 'hooded' gate as the BD Hotwire can be opened by merely brushing the rock. I believe that the hooded gate is the patent that BD holds for that product. 'Makes ya wonder why...
Zoo

climber
Fremont, CA
Topic Author's Reply - Oct 3, 2008 - 09:34am PT
EC, not sure what you mean by punishment for hanging.
Zoo

climber
Fremont, CA
Topic Author's Reply - Oct 3, 2008 - 09:59am PT
About the possibility of gate opening:

The location of the bolt is on a low angle slab above the difficult move. To clip, I had to reach out to the right so I'm pretty sure I had the gate to the left since that is most natural to me. Since the angle of the rock is low, the biner was resting partially on the side of the gate (see above comment about wiregate biners with something that protects them from the side, I think Helium biners have this). I was a little to the right of the draw when I fell so the load on the top biner in combination with the swing to the left could have opened the gate. I'll be paying more attention to the orientation of the top biner as well as the bottom biner in future climbs I'm sure.

About the force on the gear:

With gear, I'm 85 kg. My belayer is about the same, belaying from a standing position with a Guide ATC off his harness. Fall was about 3-4' on about 15' of rope (9.4 mm Beal Stinger). If someone can calculate the load on the biner from that, I'd be grateful. It is hard to estimate the time over which the impact on the biner occurred, but maybe there are some empirical charts out there that can help. Zander pointed me to some information in J. Long's anchors book that I haven't had a chance to look at yet. He thought that 2-4 kN seemed reasonable for this fall. The biner is rated 23 kN with gate closed, 8 kN with gate open, and 8 kN in the short direction.
ec

climber
ca
Oct 3, 2008 - 10:13am PT
Zoo,
My Bad, I misunderstood your account 'before the fall'.

 ec
Chris McNamara

SuperTopo staff member
Oct 3, 2008 - 10:19am PT
scary. i had a non-wire gate biner break during a fall. I think it was because the "biner chatter" caused by the rope running through. it was then loaded when the gate was open. i think.

after that i favored wire gate biners because they have less biner chatter. but this forum topic/post potentially pokes a hole in that reasoning.
rhyang

climber
SJC
Oct 3, 2008 - 10:49am PT
Scary, glad you are relatively unhurt. Curious to know what Mammut will say..

One small nit - you probably meant to say September 27 above.
Clint Cummins

Trad climber
SF Bay area, CA
Oct 3, 2008 - 10:58am PT
Zoo,

Thanks for the detailed description.

Do you remember what kind of bolt hanger it was?


some common hanger types

Like Curt (dirtineye) suggested, maybe the biner got stuck in some orientation in the hanger and got torqued in an unusual load.

You said the gate was on the left side. Was the gate opening on the top or bottom? (It would be on the top if you clip the bolt and do not rotate the biner).


It sounds like this is how you were clipped (gate up and left).

I recall some biner breaking accident described on rockclimbing.com, where the biner got opened by the hanger. You could even get a situation where the notch on the nose of the biner is caught on the bottom of the hanger (with gate open on the other side of the hanger). That would probably be one of the weakest positions for the biner.


Notch loaded on hanger. It's hard to get the biner into this situation. It might happen if you were clipping desperately and not able to see it very well (probably not the case for you). But for some shapes of hangers and biners, it might happen on rotation of the biner during a fall?

Here is a link to other situations where biners have broken:

http://groups.google.com/group/rec.climbing/msg/e5ed0996879e0f12
(Chris Harmston, "They all broke in open gate.")
Anastasia

climber
Not there
Oct 3, 2008 - 11:18am PT
Bump...
I want to hear what Mammut can figure out from this. I too have a great love for their ropes.
AF
Zoo

climber
Fremont, CA
Topic Author's Reply - Oct 3, 2008 - 11:51am PT
To Rhyang: Good call, September 27th.

To Clint: I don't know what kind of bolt hanger it was. I plan to go back to check out the location of the bolt, take some pictures, etc. I don't know when I'll find the time though. The gate was opening from the top. I rotate my biners when I clip my own gear, I'm not sure why I didn't on that bolt. Torquing in some abnormal way is quite possible. I think the biner was hanging free in the hanger, but who knows what happened after I slipped.

n.b. Mammut makes a Bionic Wiregate Biner that has a hood over the gate which eliminates some of the problems discussed here. The extra 7 grams/biner over the Moses seems less important to me now. Also, the open gate strength is 10 kN instead of 8 kN.
paganmonkeyboy

climber
mars...it's near nevada...
Oct 3, 2008 - 11:59am PT
similar to what clint mentions, i've noticed some biners that have that little rope 'pocket' on the end seem to get loaded weird on hangers in certain orientations...anyone else seen this too ?
MisterE

Trad climber
My Inner Nut
Oct 3, 2008 - 12:06pm PT
I was thinking notch loading as well, but also possibly a side-impact combined with gate compromise?

Glad no one was seriously injured.

Erik
dirtineye

Trad climber
the south
Oct 3, 2008 - 12:25pm PT
yeah, the fact that your fall only created 4 kN max really makes for some weirdness.

Thanks for the good follow up.
Personally, I love wiregates, only I use the ball lock things from DMM, and a few heliums from WC.

Chris, this situation is so bizarre that there really can't be any rational reason to give up on wiregates, unless your wiregates are just crappy ones.
dirtineye

Trad climber
the south
Oct 4, 2008 - 08:02am PT
Shameless bump, cause some moron(s) bumped a pile of USELESS OLD climbing related threads, and ran the current stuff off the front page.

halfhitch

Trad climber
Steamboat Springs, CO
Oct 4, 2008 - 12:09pm PT
From Clint's picture depicting the clip of what essentially is a "D" shaped biner, It looks fundamentally wrong to me in that a "D" biner's max load is at the apex - one contact point with the hanger instead of two contact points shown?
HighDesertDJ

Trad climber
Arid-zona
Oct 4, 2008 - 01:49pm PT
Clint- Great pics man. Look at that leverage!!!
Anastasia

climber
Not there
Oct 4, 2008 - 03:36pm PT
BUMP

labrat

Trad climber
Nevada
Oct 4, 2008 - 04:23pm PT
I seem to remember that the hanger on that bolt is loose, this just seems to add to the variables. I hate going that way and now I have one more reason.
Erik
chainsaw

Trad climber
CA
Oct 4, 2008 - 05:46pm PT
I think the lesson here is never trust your life to Off Brands. Mammut is not known for hardware. I don't know but they probably dont even make those biners themselves. If it has to hold stick to Black Diamond, or Petzel and you cant go wrong. The testing regime that black diamond uses is far superior to other companies'
I have seen Omega Pacific biners break too. Black diamond certifies other companies equipment for them because they have established the best industry standard.
Is it possible that the unit was used to pull a car out of a ditch?
dirtineye

Trad climber
the south
Oct 4, 2008 - 05:54pm PT
Danger Will Robinson!!! Last post smells like... dogshyte!
chainsaw

Trad climber
CA
Oct 4, 2008 - 05:56pm PT
Hugs and kisses to you too nice guy
hoipolloi

climber
A friends backyard with the neighbors wifi
Oct 4, 2008 - 06:10pm PT
In regards to the first photo posted by Clint. I have been told that the way the carabiner is clipped in that picture can 'technically' cause cross-loading forces on the biner because of the two points of contact on the carabiner (each piece of the metal of the hanger touching the carabiner).

This was pointed out to me by a Spanish friend who did a lot of sport climbing and was training for guide certs in Spain. Not sure about the validity of the statement. Thoughts?
WBraun

climber
Oct 4, 2008 - 06:27pm PT


Hmmmmmnnnnnn?

Clint, the biner in this photo looks like it could be getting a dangerous leverage type load if the bolt hanger was angled such as this photo's demonstration?

Just looks that way to me ..... ?????
hoipolloi

climber
A friends backyard with the neighbors wifi
Oct 4, 2008 - 08:13pm PT
thanks for the picture Werner. Thats exactly what I was trying to say. My friend said that force is equal to cross loading.

wonder if its true.

or does this specific carabiner just suck balls?
slobmonster

Trad climber
berkeley, ca
Oct 4, 2008 - 08:29pm PT
I suspect that this biner does not (simply) "suck balls."

dirtineye

Trad climber
the south
Oct 4, 2008 - 08:38pm PT
I suggest that you are right, but that chainsaw does.
Greg Barnes

climber
Oct 4, 2008 - 10:08pm PT
chainsaw, the biner that Chris Mac broke was a BD.

The biner that the Korean dude broke on Shaky Flakes was a Lucky rated to 8kN gate open (no deformation on the gate, it looks like the biner broken here). We have it somewhere.

A friend broke two blue-gate REI biners in one fall - those are the mid-90s ones that look like BD light-D biners. First broke a fixed nut, then the biners on the next two pieces broke.
Double D

climber
Oct 4, 2008 - 10:37pm PT
Scary thought but it makes sense that it would be under a large cross-load situation if clipped that way. It's an eye opener for sure. Thanks for all of the posts. I know I will always check the angle of the bolt to biner when clipping from here on.
thedogfather

climber
Midwest
Oct 5, 2008 - 08:31am PT
I am fairly new to sport climbing and was never too concerned about which way I put the top biner through the bolt (left to right or right to left). I have recently gotten into the habit of always clipping like this after climbing with a more accomplished sport climber::


I would assume that is always the preferred way to go after seeing the double contact points that Werner pointed out that are possible if you clip like this:



Am I correct here?
MisterE

Trad climber
My Inner Nut
Oct 5, 2008 - 09:11am PT


The most disturbing part of this picture is the hanger appears to have NO BOLT!

Aside:
Some jerkwad once glued some hangers on a wall in Leavenworth Washington back in the 90's, I guess in the hopes that some sporto would clip without looking...
slobmonster

Trad climber
berkeley, ca
Oct 5, 2008 - 10:34am PT
It appears that folks forget about the top 'biner pocket in their quickdraws. It is "loose" (i.e. no rubber band thingie) to facilitate spinning the 'biner, and avoiding the scenario pictured above.
dirtineye

Trad climber
the south
Oct 5, 2008 - 02:11pm PT
Bump for a real, non-trivial, non-recycled climbing topic.
thedogfather

climber
Midwest
Oct 5, 2008 - 06:36pm PT
slobmonster, I always assumed the loose end of the draw allows the draw to freely hang below the biner vs the tight end that could cause some leverage issues. I don't think draws like this Petzl one would really facilitate rotating the biner every time you clipped.


I would still like to know if it matters which direction you clip a draw into a bolt that is oriented the way the one is above.
JuanDeFuca

Big Wall climber
Stoney Point
Oct 5, 2008 - 06:47pm PT
This is such a cool thread. I love gear failures.
Really.

Looks like geometry played a big factor.

Juan
jbar

Mountain climber
Inside my head
Oct 5, 2008 - 07:03pm PT
Clearly the butterflies in thedogfather's photo were contributing to his protection.

Clint's pics are awesome. I clipped short once. Once. Thinking of the leverage tearing the biner open is scary.

I also have often wondered about the biner position in the newer bolts like in Wbraun's photo. To me the 45 degree angled bolts just didn't make sense. Harder to clip and it seems like they would have more of a tendency to twist under stress.
slobmonster

Trad climber
berkeley, ca
Oct 5, 2008 - 07:30pm PT
quote
"I would still like to know if it matters which direction you clip a draw into a bolt that is oriented the way the one is above. "

It only "matters" if you fall, right?

A few years ago BD began selling all their draws w/ the 'biners facing the same way. They included a fairly cogent explanation as to why... someone will probably dig this up, I think the(ir) primary concern was the bolt-end 'biner unclipping from the hanger. On a route that veers right, everything gets clipped w/ the gates facing left.

(I've always had my draws with biners facing in opposite directions. This allows for easy spinning of the bolt-end biner, so (if needed) the narrow side of the biner's offset shape is hanging off the bolt.)

As for "why" bolt hangers are commonly installed with a counter-clockwise bias, this is so they won't spin loose when loaded. Still happens, unfortunately, but this would be a discussion for another nerdy post.

dwm

climber
Oct 6, 2008 - 02:32pm PT
Slobmonster --

Based on your post I emailed BD and received this reply from Jeff Maudlin at BD (note disclaimer that this correspondence is personal
opinion and NOT an official statement of Black Diamond Equipment Ltd.) --

Hi Dave,

Thanks for writing. Must have been scary for sure. I'm glad everyone was ok. Mammut is a great company and I'm sure they will have some good info for you.

I dont believe we have an "offical" stance on the quickdraw orientation matter...other than that's the way we package and sell them. I also don't recall us ever stating a reason to do it one way or the other in any catalog. There are decent arguments to have draws oriented with top biners in both directions depending on the situation and scenario in front of you.

Personally I like the gates of both top and bottom biners facing the same way. I always face the gate on the bottom (ie. rope) biner the opposite direction of the way I'm climbing (ie. route goes left, I face the gate to the right). Reason why I like both the biners with gates the same way is it's then easy to know which way to clip the bolt or piece of gear, etc with the top biner as a reference.

We don't spend alot of time testing all kinds of orientations in terms of a carabiner in bolt hangers, or have any data to share on the subject. Generally our feeling is that backclipping and interaction with the rock (in an adverse way) should be the foremost thought here and is always to be avoided. So this should always be your prime consideration no matter how you set up your draws. If there was EVER any concern that a gate may open, a locking carabiner should be used.

Carabiners can break for many reasons, generally related to weaker gate open strengths (gate not fully closed during loading). This can include:

* sticky gate action (very common)

* caught in a bolt hanger

* caught in a quickdraw or piece of gear

* rubbing against rock during loading causing gate to slightly open.

Here is a very dated discussion (about quickdraw orientation) here:

http://www.tradgirl.com/climbing_faq/safety_2.htm#unclipping

You'll have to scroll down a bit to find it. There are even some thoughts there from one of our former QA Managers, Chris Harmston, on the topic.

Best Regards,
Jeff Maudlin
BDEL

Jeff Maudlin (jeffm@bdel.com)
http://www.blackdiamondequipment.com

Black Diamond Retail, Inc. (801) 278-5533 (phone)
2084 East 3900 South (801) 278-5544 (fax)
Salt Lake City, Utah 84124


DISCLAIMER: Unless otherwise indicated, this correspondence is personal
opinion and NOT an official statement of Black Diamond Equipment Ltd.
-----------------

Thanks Jeff --

That's helpful. If you don't mind, I'll paste that in to the Supertopo discussion thread where others can profit from it as well (with your permission).

Best regards,

Dave
------------------

Dave - it's fine. There's not really anything here that isn't true or common knowledge. It's possible that if this was in a catalog sometime I just don't remember it or it was a "tech tip" something like that. For sure we've never said you HAVE to set up your draws specifically this way or that way. It's a judgement call at some point. I'd rather people pay attention to keeping the action on their biners smooth (no sticky gates), avoid backclipping, and judge how the rock could interact with a carabiner if loaded it (not always easy to do). Hope it helped you out.

Jeff
paganmonkeyboy

climber
mars...it's near nevada...
Oct 6, 2008 - 03:17pm PT
that weird points-of-contact thing was exactly what i was talking about with the biners that have a rope dent in the big side - the dmm prowires and oxygens on my rack have them, and you do have to clip them a certain way to bolts or you see that 2 pts of contact leverage action for sure...
mongrel

Trad climber
Truckee, CA
Oct 6, 2008 - 05:02pm PT
Plenty of excellent-brand/model of biners have broken in real climbing situations. Excellent input from many sources here. Short version seems to be:
1. Most biners are strong enough with the gate open for anything but a really severe fall (many have the same gate open rating as the max impact force for most lead ropes).
2. The most likely way to failure is the biner getting twisted and loaded simultaneously. If the gate is being impinged upon sufficiently to be pushed open, then you've also got a twisting load which is probably much more critical than the open gate.
3. Much less likely, but still presumably possible, would be loading with two points of contact such that the biner kind of locks in place, then you have leverage on it and pdoink! more air.

All of these problems are by far more likely to occur if the wide end (gate) end of the biner is at the bolt (piton, or ice screw). Flipping the biner over takes maybe a couple seconds - say five to eight minutes over the entirety of a 15-pitch climb. But it also matters which way you're headed (and of course much more so if you don't flip the biner): for firmly fixed pro (bolt, pin, or screw), this should be away from the gate, see the butterfly photo above. If the biner tips upward in the direction of the gate, you can definitely result with the last image in Clint's series, with the gate caught on the edge of the hanger: pdoink! more air

Read also the comments on the link in Clint's post, self-unclipping of the rope is not uncommon at all if you use the full-tacked dogbone draws. I have a bunch and use them, but cautiously.

And don't fall so much!

dirtineye

Trad climber
the south
Oct 6, 2008 - 05:12pm PT
"1. Most biners are strong enough with the gate open for anything but a really severe fall"

OK, so far so good....

"(many have the same gate open rating as the max impact force for most lead ropes). "


BUT That last bit is not a correct way to think about this.

THE rope will ONLY allow it's max impact force to be felt by the faller, no matter how much force there is in the fall. PLUS, the rope WILL NOT BREAK. That's WAY DIFFERENT from a biner breaking at the max impact force of a rope.

And don't even try to say the biner bears the same force as the faller, cause the rope is thought the biner, so there is not quite but close to 1.6 times as much force on the biner that holds the fall (until it breaks anyway) as on the faller.
dwm

climber
San Mateo, CA and now Paso Robles
Oct 11, 2008 - 11:06pm PT
well -- that was the only fall either of us had on that climb.

In the interest of fleshing out the "TR" part of the thread, here are some photos from that climb besides the broken biner part.

Here's a photo of Sugarloaf and Kyburz, taken back at the end of June on a day we went to Lovers Leap:



Here is the Scheister route, showing the belay stations:



Here is the view from the base of the route. What I really think is cool about this route is the way the granite column hangs over your head up to the second belay station. You can see which column is which in this photo, where the "profile" of the route matches up with the way it looks as you are climbing it:



Here is Mike leading through the chimney (photo taken from base of the route):




Here's the view upwards from the first belay station (marked with a small "1." on the photo showing the route). You can see the way that big granite column leans over the Scheister route, and that you are much closer to it on the second pitch.



Here's another view of the route looking upwards from the start of the second pitch (Mike leading):



At the second belay station, you are even with that top of the column, as you can see here in this photo looking outwards from the belay station marked with a small "2." on the route photo. Here's Mike at the second belay station:



Unfortunately, we don't have too many photos from the third belay station -- we were busy with the broken biner at that point.

Here is Mike at the end of the route:



And here's me at the end of the route:



pcousar

Sport climber
White Salmon, WA
Jul 13, 2009 - 04:00pm PT
did you ever hear back from Mammut??
labrat

Trad climber
Nevada, CA
Jul 13, 2009 - 08:26pm PT
Bump
Paul_in_Van

Trad climber
Near Squampton
Jul 13, 2009 - 11:39pm PT
Bump, would also like to hear a resolution on this one.

P
mucci

Trad climber
The pitch of Bagalaar above you
Jul 13, 2009 - 11:51pm PT
Would orienting the biner down and out be a better option? I guess you still run the risk of the runner or dog bone sliding off, but may prevent the breakage.
Zoo

climber
Fremont, CA
Topic Author's Reply - Jul 20, 2009 - 12:47pm PT
Sorry that I forgot to post this when I received the email from Dave at Mammut. Here is his response from November of 2008.

"Hi Michael,

I just got back from Switzerland where I was able to discuss the broken carabiner with the product manager there and see some test results. The metal on the biner was fine, and both the original batch test results and a new set all came back fine.
Based on the type of break exhibited by this carabiner all signs point to an open-gate failure caused by the carabiner being opened by coming into contact with the rock during the fall, possibly with the load occurring farther away from the spine than usual for the same reason.
They are waiting for the next production batch to come available (a few weeks) so they can run some comparative tests, and will compare the breaks during testing of the new batch with yours to determine a final cause of failure and forward some close-up photos of the breaks to me to illustrate for you their reasoning.
I'll keep you posted, but at the moment we think this was a fluke accident that could have happened to any carabiner—let me know any questions.

Dave"


I haven't been in contact with Dave since then.

MikeZ
labrat

Trad climber
Nevada, CA
Jul 20, 2009 - 02:02pm PT
Thanks for the update.
At least they got back to you.
Erik
Rokjox

Trad climber
Boys I'dunno
Jul 20, 2009 - 02:15pm PT
I think this is the natural conclusion of trying to mill every last milligram from a biner. Your crab ends up being able to pass a carefully designed pull test, but the slightest non-optimal stress and the thing fails.



Leave a little meat on those bones. I also, for similar reasons, I don't like wiregates at all. They belong inside a gym, like those tiny g-string loops that some use for quickdraws.

The weight savings isn't as important as the burliness of the durability factors. If it is becoming so important to place each and every biner in a particular orientation to keep from being killed, we need to make less fussy gear.


Too many stinking rules to remember when you are peeing yourself at the outside of the curve of your comfort zone.
GOclimb

Trad climber
Boston, MA
Jul 20, 2009 - 02:38pm PT
It seems to me that no-one ever answered this question:

With gear, I'm 85 kg. My belayer is about the same, belaying from a standing position with a Guide ATC off his harness. Fall was about 3-4' on about 15' of rope (9.4 mm Beal Stinger). If someone can calculate the load on the biner from that, I'd be grateful. It is hard to estimate the time over which the impact on the biner occurred, but maybe there are some empirical charts out there that can help. Zander pointed me to some information in J. Long's anchors book that I haven't had a chance to look at yet. He thought that 2-4 kN seemed reasonable for this fall. The biner is rated 23 kN with gate closed, 8 kN with gate open, and 8 kN in the short direction.

So - to answer it now: If your fall was four feet before the rope started to catch, the climber side of the rope would feel around 4kN, the belayer would feel around 3kN, and the top biner would feel around 7kN. That's close enough to its gate open strength that if the hanger was slightly off-center, I could easily see it snapping the biner with no defects whatsoever, so long as the gate was open.

And to answer what I think is the underlying question - the same thing would happen to virtually any biner on the market, if the gate had gotten pushed open on it.

GO
Mungeclimber

Trad climber
sorry, just posting out loud.
Jul 30, 2009 - 12:11am PT
final final word?
squishy

Mountain climber
sacramento
Nov 25, 2009 - 08:40am PT
So, what's the word?
Toker Villain

Big Wall climber
Toquerville, Utah
Nov 25, 2009 - 05:31pm PT
Saw the title and thought that this might be about a jewish personal injury lawyer.


Glad everyone is OK.


Two lessons here;

1) back shlt up

2) Its good to have Clint Cummins on the taco.
Zoo

climber
Fremont, CA
Topic Author's Reply - Dec 2, 2009 - 08:58am PT
I emailed Dave from Mammut again. He apologized for not following up andsaid he planned to be in Switzerland next week. He said he would look to see if any of the testing mentioned in my post from last July had been done. I'll try to follow up with him again in a couple of weeks.
cliffhanger

Trad climber
California
Dec 2, 2009 - 02:26pm PT
I think the thin hard sharp steel of bolt hangers in general is a big part of the problem. The carabiner is soft aluminum. Alot of force, a little twist, and the bolt hanger will cut right into the aluminum.

Put permanent steel rings or chain repair links on all bolt hangers:



http://www.cvfsupplycompany.com/quli3qulichr.html

http://www.thefind.com/pets/info-chain-repair-link-steel



edit: they could be made with a dull gray finish to blend in. Or the hanger could be made with a welded ring by the manufacturer, the whole works being dull gray.

edit2: these descending anchors could be used as a standard bolt hanger:



http://climbinggearinc.com/descending-anchors-p-488.html?zenid=b1ff0d69d3f49a261eb29dbf4594f9c5

http://store.everestgear.com/climbing---mountaineering-bolts---hangers.html
Mungeclimber

Trad climber
sorry, just posting out loud.
Dec 2, 2009 - 02:33pm PT
No cliffhanger, do not.

we already "litter" enough with hangers. we don't need extra pieces of shiney screw gates hanging there too.


use smooth radius hangers if you'd like. Start with replacing the old thin rusty hangers. may as well fix the bolt while at it.


Pate

Trad climber
The Lost Highway
Dec 2, 2009 - 02:40pm PT
Do you have any sharper photos of the biner? I'd love to see closely what the metal around the fracture looks like.
Doesn't sound look like the gate was open, I've seen a few broken 'biners where that had been the case, and the biner is always significantly bent, not broken clean like it appears yours was.

Did you ask to have the biner returned to you?
Brian Hench

Trad climber
Anaheim, CA
Dec 2, 2009 - 04:04pm PT
I think that our gut instincts about a burlier carabiner being better than a light one are likely to be meaningless. There is so much design put into modern hardware you can't just eyeball it. It's better to trust the engineers and the testing labs and focus on the things you can manage best yourself, which is biner orientation, sling type and length and other factors.

In the OP, the biner which failed was the first one from the belay when the FF was the highest. One thing to consider in such situations is to use a locking carabiner on the bolt. I've climbed with guys who carry one or two draws with lockers and use them on their first one or two bolts, usually on slab climbs.

I doubt most people would consider doing this, but it is one solution.
GhoulweJ

Trad climber
Sacramento, CA
Dec 2, 2009 - 07:44pm PT
These ultra light biners can be great!

But I think there is a balance between mass and durability.

Take a look at this link:

http://www.omegapac.com/op_climbing_dash.html

it's built to take the punishment that might cripple other anorexic 'biners.
Zoo

climber
Fremont, CA
Topic Author's Reply - Dec 16, 2009 - 09:00am PT
Here is the latest I received from Dave at Mammut.

If you look at the pictures you can see some patterns—the dynamic breaks with the gate open virtually always break in the same place, right where yours did. This is the most common type of break, as it takes far less of a load to break an open-gate biner, and if the load is somehow applied out onto the nose (i.e. not aligned directly along the spine) it can take a truly small load to break—it’s not common by any means but it is not unheard of. Closed-gate breaks are FAR less common and pretty much always show significant deformation of the overall carabiner shape, and on a pinned gate or a wiregate like this they pretty much always break on the nose of the carabiner, as you see in the photo.
Generally in a real climbing situation it isn’t realistic to generate that much load in a static manner until you get into wacky hauling situations, etc.

The scenario that your carabiner broke under is actually the most common one for a biner to fail—a swinging fall causes the gate to rub against the rock, as the biner swings the rough rock pushes open the gate, and the load ends up applied out nearer to the nose of the biner than the spine (either due to the way the biner hangs in a bolt hanger or because a sling is pushed out to the side, etc), and near a belay/tied in tight so there is less rope out and less dynamic element to the belay to absorb the force of a fall. Under these circumstances it’s unfortunately not too difficult to break a biner if all the stars are aligned just the wrong way—for this reason I would recommend always doubling up pro on critical pieces or using a lightweight locking biner or something like this, especially if there are terrain features that could come into play against a biner.

The batch testing we conducted showed that there was nothing abnormal in the metal itself, and the breaks we conducted again on our stock from that batch confirmed this. All the breaks were well within the parameters we expect and well above the stated loads printed on the biners.











Mungeclimber

Trad climber
sorry, just posting out loud.
Dec 17, 2009 - 12:00am PT
Fascinating. Good follow up it would seem from mammut.



This explains the niceness of the helium nose guards. hrm


I wonder what the rating was on those dynamic tests as compared to other biners of slightly bigger stock or shape changed?
bmacd

Trad climber
British Columbia
Dec 17, 2009 - 05:45pm PT
So in that case, is a wire gate is more likely to be sprung open when dragged across the rock as it would only take a little nubbin to hook the wire and pull it out of place ?

A non-wire gate biner may require a higher nubbin size threshold to open it as it dragged across the rock. Would the rounded surface area of a non-wire gate deflect more nubbins than the wire gate and therefore be less prone to opening.

I thought that the premise of wire gates was they are less prone to opening ? Perhaps the wire gates were only tested in free space and not in rock surface contact type situation ?

Not that I know much about it .... just speculation
Matt's

climber
May 17, 2013 - 01:58pm PT
bump
patrick compton

Trad climber
van
May 17, 2013 - 03:24pm PT
^^ seems to be a lot of mammuts breaking huh?
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