Discussion Topic |
|
This thread has been locked |
Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
|
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.
|
|
Brian in SLC
Social climber
Salt Lake City, UT
|
|
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
|
|
JLP
Social climber
The internet
|
|
"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?
|
|
Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
|
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.
|
|
Evan Jackson
climber
Austin, texas
|
|
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.
|
|
Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
|
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.
|
|
graniteclimber
Trad climber
Nowhere
|
|
Hardman Knott: "No need for name-calling"
That is funny coming from you after your Slime post calling just about everyone "morons" and "idiots."
|
|
Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
|
What's even funnier is how you edited your post the other day after doing essentially the same thing...
|
|
graniteclimber
Trad climber
Nowhere
|
|
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.
|
|
JLP
Social climber
The internet
|
|
I have been here many times. This is the point where we can either:
1) Assume there is not a problem, even though there was a failure.
2) Wait for some mole to return from 3 months in the lab and quote mind numbing statistics about how there isn't really a problem.
3) Wait for another mole to return from 3 months of Ansys simulations. He'll put on a ppt show that will put your best 4th of July to shame. Someone later will find he had to change all his material constants to meet the statistics guy's numbers.
4) Fix the obvious problem.
I say fix the ring feature and get the welding process under control.
Did someone say these bolts are no longer and this one was "The Last One in the Bin" and marked differently to boot? Holy cow if I haven't seen that before as well. I say this bolt was just as likely from the reject bin - the guy who knew WTF left long ago and some scavenger grabbed all the sh#t from the lab and shipped it.
|
|
Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
|
Graniteclimber - from that very page you linked:
Ushba Mountain Works gratefully acknowledges the hard work, research, expert opinions, and contributions of John Byrnes, Skip Harper, Sam Lightener Jr., and Mike Shelton. Numerous other individuals such as Eric Hirst, Marty Karabin, and Josh Blumenthal also contributed.
|
|
Evan Jackson
climber
Austin, texas
|
|
“Thanks for the update. No need for name-calling.”Apologies; just a play on words not an insult.
"I thought C-100 had been out of production for many years. What was the expiration date on that tube?"
The bolt was placed years ago. No way of knowing the expiration date but we always check it.
"How do you explain the bend in the bolt?"
I can't. Residual stress is a definite possibility. I've machined parts to a thousandth of an inch only to have them go significantly out of tolerance the second I start machining a new surface. I’ve even had parts go out of tolerance simply by polishing a surface. Removing a few thousandths of an inch is enough to remove locally deformed material and relieve residual surface stress created during the machining process. These weren’t skimpy parts either, some were 3” thick pieces of mild steel
"So was the shaft exposed prior to breaking or not?"
No. FYI we have a local reporting system for suspect bolts. It works well and our climbing community is very close. No visual warning was present.
"If the rock withered away so that an inch or more of the shaft was exposed" It didn't. Please stop speaking hypothetically.
"Please, please show me ANY bolt that wouldn't bend if subjected to such force with an inch of shaft exposed."
Powers, 1/2" by 3-3/4" expansion. Have you ever tried to pull bolts? You'd be amazed at how strong they are even when they're just hammered into the rock and not even tightened down. I've shanked these guys with a 4lb sledge, taken 4' static falls on them, pried with a crowbar, and nothing has happened. Many times, a bolt will pull partially out and then get stuck sometimes leaving half an inch or more and the opportunity to test crappy placement scenarios.
“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”
You’re not looking at the big picture. This might be true (but it’s not) if you were comparing 2’ of rope to 40’ of rope, but not 42’ of rope compared to 50’ of rope. Furthermore, loading conditions change once slack is paid out. In the roof, if you are taking a fall from the lip, 10’ of slack will catch with the rope in a load rate near vertical orientation compared to 2’ of rope in which a swing and low impulse is applied.
Think about it this way, would you rather pull out ten feet of slack and take a fall while you were next to the bolt so the rope formed a u shaped bend or would you rather take a fall while you were as far away as possible with the rope horizontal (assuming no obstacles)?
|
|
pud
climber
Sportbikeville
|
|
|
|
Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
|
Since this is the first I've heard of a Tortuga bolt failing, and many of them reside at Mickey's Beach
(my local crag), I would hardly call it beating a dead horse. The more information, the better.
|
|
Chiloe
Trad climber
Lee, NH
|
|
That substantial bend in the broken bolt seems to be the big mystery. By all accounts
(solid, straight vertical placement; vertical angle of pull) it should not be there.
But there it is.
Since my photo of a pristine Tortuga bolt has been mentioned a few times, here's a closeup
from that photo showing the weld and first groove.
The little white marks you see are just surface scratches.
|
|
Chiloe
Trad climber
Lee, NH
|
|
Although I can't guess what happened to that broken bolt, it's worth reiterating that
the Tortuga was developed to solve a very real and potentially deadly weakness of steel
bolts in warm marine environments. I've seen fat sport climbing bolts break under
hand pressure, while Tortuga bolts nearby still look new (and hold falls) after more than
five years in place.
|
|
Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
|
A lot of words posted to this thread, and yet I am still failing to comprehend the bend ™.
Up-thread I offered $100.00 for hi-rez photos of the bolt (pre-break) as originally installed,
which prove that the bolt was indeed seated all the way, and that the bolt was oriented
faced in the direction best suited for the forces it would be subjected to.
In the unlikely event that someone actually comes up with such pics, I would ask that
the money be donated to rebolting efforts, although that would certainly be up to you.
Also, my offer of $10.00 stands (the cost of 2 beers plus tip) for close-up pics (post-break) of the hole
that held the bolt, and preferably from a view which shows the angle of the bolt in relation to the rock.
|
|
Ain't no flatlander
climber
|
|
Graniteclimber spewed "The Ushba marketing copy recommends the ascender for roped soling "Oh my god, what an idiot" Hardman/Slime is. They were wrong."
To be accurate, the copy says it is indeed recommended for top-rope solo only. And the instructions have a very large caution that states "NEVER grasp the device during a fall!" with an illustration stating DANGER. It also warns against shock loads. The guy who decked has only himself to blame.
The bend in that bolt as well as the location of the break tells us there is more to this story than the weld.
|
|
|
SuperTopo on the Web
|
Let us know!