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Dr. Rock
Ice climber
Castle Rock
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Who is the Dr Kudos, and what did I do to his wife?
You realize each time ya tool me, that it's another bump?
Ha!
Bump on, my friend, bump on...
Hey, what about a Platinum ceiling bolt?
Any ex microwave engineers around here with exit property?
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dirtineye
Trad climber
the south
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I have informed Liberty Mountain, who handle all Ushba stuff now, about this problem, and given them a link to this thread.
We will see what they have to say, if they show up.
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HMS
Trad climber
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Found the following on http://www.bolt-products.com/Glue-inBoltDesign.htm:
"There have been a number of welded eye bolts on the market but weld failures have always been seen as a problem. One on the market (not in Europe) that I know of is the USHBA bolt made from titanium, in tests by the German Alpine Association (D.A.V.) three out of five broke at the weld at under 10kN."
So, its not that strange seeing a Ushba bolt break. But this bolt broke not at the weld but at a different place/stress-zone).
I would (and do so) use only forged bolts with the shaft comming from the middle of the eye (of the bolt), which are placed with the eye countersunk. Looks like the best solution to me - least stress while in use. Do have a look at the www.bolt-products.com website - its informative and the guy(s) know what there talking about.
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stevep
Boulder climber
Salt Lake, UT
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First, Dr. Rock, Pie are not square, they are round :-).
Thanks for the input Evan. I didn't mean to take shots at the bolter, but certainly the picture does make it look like the shaft is exposed. I'm not sure I quite understand how the bolt would bend unless it either was installed with some shaft exposed, or rock/glue later crumbled/spalled away from the shaft, thus exposing it and allowing it to become a lever while people were swinging around dogging on it.
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Evan Jackson
climber
Austin, texas
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Steve, I don't know how the shaft bent either, but believe you me, the hole is still in good condition.
HMS, there is a crack located at the weld.
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dirtineye
Trad climber
the south
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HK, can you prove that he is indeed Kodos, cause although I'm fairly certain, absolute proof would be good.
Since he's more of an a$$hole than Crowley or anyone else for that matter ever was...
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HMS
Trad climber
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To Evan: Yep, its a design fault.
Designing and placing a good bolt is tougher then it seems. No bolt/system is foolproof, unfortunately. But we should try and understand the loads in real-life situations before designing bolts. Only the best is good enough - make the bolt tougher and longer than you think it has to be.
I want the bolts I place to last at least 50 years and find it really difficult to decide what to use (and yes, budget plays a role). There is not a single bolt that works in every situation. I would like to find a cheap, forged, non-flexing, visually low-profile, HCR glue-in bolt with the shaft centered to the eye(placed countersunk and 4 to 5 inch deep) and a slightly more viscose glue than the stuff I use. The Petzl Collinox/Batinox come close, apart from the cost aspect.
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JLP
Social climber
The internet
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"Steve, I don't know how the shaft bent either, but believe you me, the hole is still in good condition. "
It's a 10mm bolt in an 11mm hole. The 11mm hole will actually be larger because that's how drilling works. The wrong bit could also have been used - 1/2" is ~12.5-13mm for example. That leaves at least 1-2mm for the bolt to bend (plenty, given the photos). You'd just have to measure it. It also brings one to question what kind glue was used and how much of it. It would appear that insufficient glue is the same as not drilling deep enough. If a 1/2" bit was used, that would also allow a lot more bending because of the increased thickness of the softer glue layer.
But who cares - the ring feature is still the most interesting thing to me. It is obviously a huge weakness. If there is a cracked weld, that's more a process control issue.
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graniteclimber
Trad climber
Nowhere
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There have been a number of welded eye bolts on the market but weld failures have always been seen as a problem. One on the market (not in Europe) that I know of is the USHBA bolt made from titanium, in tests by the German Alpine Association (D.A.V.) three out of five broke at the weld at under 10kN."
Any Taco resident have any friends in the German Alpine Association? who can get a copy of the test results?
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Dr. Rock
Ice climber
Castle Rock
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Here is a more detailed explanation of the bent shaft and the failure process:
John B Breneman,CE
Prof. of Engineering,Mechanics
Penn State Univ.
So what happens here is they take a perfectly good piece of space program Titanium, then score it, then bend the hell out of it, which it does not like, then they weld the hell out of it.
How many of the original properties do you think the round stock has retained after all that drama?
Just for gits and shiggles, a hardwood bolt was sketched, Brazilian Rosewood from Souther Lumber backed up by some Napalese Ironwood, which is then epoxied to a strip of Georgia Yellow Pine for good acoustics, turns out a half inch hardwood bolt will take 25 Kn, go figure.
Here is a link to a Nasa Database.
You can spend days just on Titanium:
http://ntrs.nasa.gov/search.jsp
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Evan - thanks for the info. I have a few questions, because I still can't picture that thing
bending the way it did, if it was indeed placed (and more importantly CURED) with the head
flush with the rock.
I will assume the following:
1. An 11mm drill bit was used, and the hole was the proper depth or slightly deeper.
2. Hilti HY-150 adhesive was used within its expiration date, and was properly mixed
via the MD-2500 dispenser, after discarding the first couple squeezes.
3. After filling the hole approx. 2/3 full with the mix, the bolt was spun slowly by hand,
perhaps 3 or 4 full revolutions until it was seated all the way. The mix overflowed
due to an abundance of the mix in the hole, NOT due to gravity making it drip out.
4. Assuming the bolt was dead vertical in a horizontal roof, the bolt would start slowly
creeping out almost immediately, for at least 5 minutes, until the mix had cured sufficiently.
Therefore, it was either held in place by hand for at least 5 minutes, or some sort of
mechanism was used to hold it in place.
The last time I priced the smallest tube of HY-150 was in 2002, and it was $27.00,
enough for approx. 11 bolts. So the idea was to rebolt as many as possible; one
because the expiration date on the tube was around 6 months, and two, once it
was opened, it was supposed to be used within a limited time frame (can't remember
off the top of my head).
The reason why Petzl had that glue recall several years ago is because there were
some failures due to improper mixing by hand. The MD-2500, and other such tools
prevent this from happening.
BTW, properly mixed and set HY-150 adhesive is not AT ALL soft, and so I am still
at a complete loss to understand how that bolt bent, if it was indeed seated all the way
in a properly drilled hole of the correct diameter.
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Brian in SLC
Social climber
Salt Lake City, UT
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Any Taco resident have any friends in the German Alpine Association? who can get a copy of the test results?
I have one version of testing done by the DAV. 2006 I think.
Here's the results from the USHBA bolt:
Ushba Haken
Ø ca. 10mm
Titanlegierung
KM 9
KM 9
KM 10
KM 24
KM 34
1,2,3,4 Bruch an Schweißnaht!
Norm nicht erfüllt!
5 Mörtelversagen (Auszug Haken aus Mörtel)
Which I take to mean, tests 1 through 4, the bolt broke at the weld. Test 5, the bolt pulled out of the mortor.
-Brian in SLC
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JLP
Social climber
The internet
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"BTW, properly mixed and set HY-150 adhesive is not AT ALL soft, and so I am still at a complete loss to understand how that bolt bent"
Not sure of the exact specs, but I will safely assume it's softer than Ti Alloy. Not soft like a pillow, but soft enough to give and allow some bending. It may even plastic deform or crack and fall out of the hole, especially if a 1/2" bit was used or even the slightest bit of the hole itself deformed - depends on the glue. Where can I buy an 11mm bit? Are they easier to find then an 11mm wrench?
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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From my own experience chopping a Tortuga set with Hilti C-100, after many blows
with a 2 1/2 lb sledge, the bolt was made to move (rotate) slightly in a radial plane.
There was no back and forth movement whatsoever. When the head finally snapped off,
it was FLUSH WITH THE ROCK - it looked nothing at all like the one shown in this thread.
As to the drill bit size, I'm pretty sure we used 7/16 bits, which is almost exactly 11mm.
I haven't seen any evidence that C-100 or HY-150 is malleable at all (when used as recommended),
and would love to be shown an example.
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Evan Jackson
climber
Austin, texas
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Hard Knock,
1. Yes an eleven millimeter bit was used. The hole was drilled until the drill chuck made contact with the rock. (I accidentally drilled a hole too shallow during my early days and will never make that mistake again.)
2. A brand new tube of glue was used. We've had tubes of glue go bad before the expiration date. One bolt even pulled out by hand despite proper mixing and ambient temperature. Thus, we buy tubes the same week of bolting. The mixing tip was used and extra epoxy was squeezed out until a uniform color was reached. Hilti HIT C-100 was used. It was purchased here. http://www.daplus.us/ShowPhoto.aspx?abi=B0E430A1765DD6F139EEA886D31104C6304EB67BA74A33239248E029D3B8B444&Partner=400240
3. The hole was filled from the back squeezing and pulling the dispenser out at the same time. The bolt was only rotated 360 degrees.
4. The bolt was held in place. We taped over the eye so no one could clip it. We returned 24 hours later to remove the tape, visually inspect, and fall test. No shaft was visible after curing. Fall testing involved several climbers taking whippers with extra slack. Some were big boys and whippers were big enough to lift belayers several feet into the air.
5. You are correct in assuming that the glue costs about 20 bucks per tube. This is only one of two glue-ins found at the wall. Thus, the intention was to glue the bolt and discard the glue. Austin has a wonderful climbing community and many donate money to bolt maintenance; money isn't an issue.
It'd be naive of me to say that nothing was done wrong but in this case, nothing stands out.
The rock is extremely soft in this area. I was and still am opposed to placing a bolt in the ceiling. I think it's unnecessary because the chains are just around the lip. However, Seismic is a beginners’ wall; the route was bolted according to audience.
The bolt was one of the last sold or manufactured by Ushba. The bolts were already taken off the market at the time of purchase. Tommy was lucky or unlucky enough to make contact and purchase one from a recommended vendor that had one remaining.
Even if the shaft was exposed or the hole contained a cavity, I find it impossible to believe that the bolt would bend under local loading conditions which were light at best.
Again, the difference in weld quality from the actual bolt and ones pictured online is dramatic and puzzling. Take note how the weld that Chiloe posted looks like a row of coins stacked up against each other. The weld on the bolt that broke looks like an amorphous blob. Furthermore, the weld on the broken bolt is partially fractured. This should never happen even if the shaft were exposed. Thus, there is more than bending and fatigue at play here.
As with many accidents, there is typically more than one root cause. This could have easily been a combination of factors but we will never know.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Thanks for the update. No need for name-calling.
I thought C-100 had been out of production for many years. What was the expiration
date on that tube? How do you explain the bend in the bolt? So was the shaft exposed
prior to breaking or not? A picture is worth 1000 words, as I said before. Surely you can
come up with one of a reasonable resolution. If the rock withered away so that an inch
or more of the shaft was exposed, and yet it continued to be dogged on by guys who weighed
220 lbs, perhaps that should have given pause for thought? Please enlighten me, I'm a little slow.
Edit: in response to this:
Even if the shaft was exposed or the hole contained a cavity, I find it impossible to believe that the bolt would bend under local loading conditions which were light at best.
Hmmm - a 220 lb guy taking repeated falls with a short amount of rope out is anything other
than what I would describe as a "light load". Please, please show me ANY bolt that wouldn't
bend if subjected to such force with an inch of shaft exposed. You wrote that you fall-tested
the bolt by taking falls with "plenty of slack"...It's the short dogging falls with minimal slack
that put the most load on a bolt, since there's less rope (and thus less elasticity) to absorb the fall.
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graniteclimber
Trad climber
Nowhere
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Hardman Knott: "No need for name-calling"
That is funny coming from you after your Slime post calling just about everyone "morons" and "idiots."
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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What's even funnier is how you edited your post the other day after doing essentially the same thing...
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graniteclimber
Trad climber
Nowhere
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Hardman, I posted a rebuke of you and Slime which I later deleted as I felt it just distracted from the topic, but now after posting something calling people "morons" and "idiots" you can upset over someone calling you "Hard Knock."
As for the post I deleted, it was intended to be funny in ridiculing you and Slime by using your own language. I didn't save the post but this is close enough:
Hardman/Slime: And NOR CAL, oh my god, what an idiot. He writes that (I paraphrase) that since his friend had an accident with an Ushba ascender while rope soloing (NOT an approved use for that device or any ascender),
The friend who had the accident was top-rope soloing. The Ushba marketing copy recommends the ascender for top-rope soloing: "These fail-safe features combine to make it an excellent choice for top-rope solo and self-belay applications" "Oh my god, what an idiot" Hardman/Slime is. They were wrong.
Edited: Added Ushba marketing copy quote and stated that the friend was top-rope soloing.
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