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BKW
Mountain climber
Central Texas
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Topic Author's Original Post - Aug 3, 2008 - 04:44pm PT
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On July 30 2008 a Ushba titanium bolt broke while in use at the Seismic Wall in Austin, Texas. Link to thread on erockonline.
The bolt had been in place for 3 years and 8 months in the roof above Diving For Rocks and saw frequent use.
Photo of broken Titanium glue in;
Just thought you might like to know in case you are considering these for your next project.
Anyone know of other titanium bolt failures?
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Looking at that photo, it appears that the bolt was placed upside down, and that it was knott seated all the way.
WTF?
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dirtineye
Trad climber
the south
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Good points knotty.
Plus there is no view of the cross section, so it's impossible to guess about failure mode.
By that I mean, was it a manufacturing defect that contributed (agree about the installation being wrong) or what?
BTW, it's Ushba.
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pud
climber
Sportbikeville
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Good point HK,
and from the looks of the bend, there must have been serious leverage issues with its placement.
Lucky someone wasnt hurt or worse.
I would not blame the piece rather the way it was placed.
Titanuim is brittle compared to mild steel.
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dirtineye
Trad climber
the south
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well that link says the bolt was in a ceiling and that people would clip it and hang and twist on it (this went on for years and frequently they say) while they figured out the crux to get out the roof.
Metal fatigue anyone?
Titanium is no different from a coat hanger in this regard. If you stress either one over and over in the same way, eventually, they break. It just takes longer to break the titanium.
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BKW
Mountain climber
Central Texas
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Topic Author's Reply - Aug 3, 2008 - 05:18pm PT
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Thanks for the spell check Dirt.
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dirtineye
Trad climber
the south
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I love the comment about titanium being brittle.
There are harder Ti alloys, but TI is most often NOT brittle, rather the opposite.
In fact, one of the selling points on the TI pitons (not that I can find em any more) is that they will follow the crevice like the old iron ones did.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Locker - I think we're all capable of clicking on the link in the OP and reading that thread;
now we have to scroll through the whole thing again to read the subsequent posts here.
Can you please delete it? (and I'll delete this post - thanks).
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Double D
climber
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Can't imagine titanium bolts if they are in any way similar to the titanium pins I've tried BITD. There's zero malability in them! They have to carve out the rock to even stick. They would ring right off the bat and clean with one stroke.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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I'm calling bullshít on this "bolt failure". There's no way in hell that thing was installed properly. No way.
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dirtineye
Trad climber
the south
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DD, what brand were you using?
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pud
climber
Sportbikeville
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We frequintly use titanium fasteners on the larger gimbles we assemble in my line of work. I have seen titanium bolts break and low carbon steel fasteners elongate and not break under the same forces.
Not a guess.
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Double D
climber
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"DD, what brand were you using?"
They were Russian from a pair of climbers in the late '70's who, if I remember right, belayed with the rope just wrapped around their wrist and forearms. Anyway, they didn't work in Yosemite worth beans because they were way to rigid. I think we threw them away.
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dirtineye
Trad climber
the south
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That's way different from the ones I bought from Ushba when they were still a going concern. Mine were very soft.
The ones I bought from Uralalp, later were still soft but htey had choices of harder if you wanted that.
But here's some info about Ti alloys from Ushba's old site.
ALLOYS: When discussing titanium, one must realize that Ti can take many different forms (alloys). Ti combines well with most metals and, depending on the recipe used to create the soup (alloy), Ti can exhibit any number of characteristics in a variety of applications. For example, the ‘commercially pure’ (CP) alloy, which is roughly 99% titanium, is relatively soft. Conversely, the alloy commonly known as ‘Ti64’ (Ti-6% Aluminum-4% Vanadium) is commonly used as a lightweight substitute for steel. While the strength of 316 stainless steel is about 70,000 psi, Ti64 has a tensile strength of approximately 135,000 psi. In short, a variety of Ti alloys are available, but selecting the proper alloy for a given application depends on the desired attributes of the finished product. The key to utilizing its unique properties is more in product design, rather than simply substituting titanium for another metal.
MECHANICAL CHARACTERISTICS: On average (depending on the specific alloy), Ti is as strong as steel, yet 40% lighter. It is immune to corrosion from salt water and most industrial and organic chemicals. Also, it is a "self-healing" metal, meaning that scratches/abrasions on the surface finish are immediately ‘healed’ in the presence of oxygen or water (no oxidation or rust). Depending on the product design, heat treatment, and alloy used, Ti can be soft or hard, flexible or stiff, as heavy as steel, or as light as aluminum. In short, it is a versatile material which can exhibit a variety of mechanical properties. For example, Ushba’s new Ti-Spec alloy offers an increase in strength which is nearly double of that found in previous Ti screws (65 ksi/450 Mpa for Ti-Spec compared to 35 ksi/240Mpa for generic Ti)!
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Dr. Rock
Ice climber
Castle Rock
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If you weld Titanium, you will probably lose any heat treating, to various degrees.
Some people re heat treat after welding, but this is an extra step.
I do not know how that thing was made, but if it is in a roof, why not use something that will handle the traffic?
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Nor Cal
Trad climber
San Mateo
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I don't like Ushba products. A partner was solo top roping on an ushba ascender and had an unfortunate accident. He fell and the ascender did not catch him and he hit the ground breaking both feet.
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stevep
Boulder climber
Salt Lake, UT
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Not sure what Ti alloy those Ushba bolts are made from, but if it's 6/4, that's not particularly brittle. Very expensive bike frames are made from that, as well as some components. It has a reputation for being strong, light, and comfortable/compliant. Not stiff/brittle.
That said, anything will fail given enough of a particular stress. Don't know that I would see this as anything other than an exception incident.
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rick d
climber
tucson, az
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so was it a sport climb?
if it failed, would you hit anything?
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Nor Cal wrote:
I don't like Ushba products. A partner was solo top roping on an ushba ascender and had an unfortunate accident.
He fell and the ascender did not catch him and he hit the ground breaking both feet.
I have used an Ushba Ascender a good bit without incident, including top-rope soloing the East Wall
at Lover's Leap on a 400' static line, and top-roping the last pitch of Moonlight Buttress in Zion.
So I suppose I must be lucky to be alive. Still, it seems crazy to knott have some sort of backup,
as you are trusting your life to the device locking, and you are trusting your life to nothing else
going wrong, such as the carabiner getting cross-loaded and failing, ect - irrespective of
what top-rope soloing device is being used.
A simple backup––such as a Tibloc on a separate biner––would have prevented the accident described above...
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drgonzo
Trad climber
east bay, CA
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people would clip it and hang and twist on it (this went on for years and frequently they say) while they figured out the crux to get out the roof.
"People?!?!?" More like freakin' hangdog sporty boys... ;-)
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