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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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dirtineye
Trad climber
the south
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Sport climbers are people too.... well sort of.
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the kid
Trad climber
fayetteville, wv
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this looks like a standard weld shut to me..
Here at the new river gorge, when we use glue in's they are petzl stainless steel units.. i would take stainless over ti any day..
ks
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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All the discussion of metallurgy and sport-dogging is interesting, but is completely irrelevant to this case.
Take another look, and please explain WTF is going on here:
There's no question that that is an improperly placed bolt (assuming that that bolt was actually placed somewhere).
Failing an explanation, I'm inclined to suspect that this whole story is a Bullshít Troll™ (or part of a smear-campaign against
Ushba). I'd love to hear from the person who actually "placed" that bolt, but I'm knott holding my breath...
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Greg Barnes
climber
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Kurt, any day except when you're climbing in warm seaside environments, I hope? I've seen glue-ins broken off at the surface of the rock in Thailand, and Petzl folks went down there years ago to confirm that stainless steel bolts were shattering within only a few years. The exact mechanism is still being investigated, so there's a slight chance that you could see similar results with stainless steel in non-seaside warm environments if there are just the right chemicals present. http://www.safeclimbing.org/education/deepbluesea.htm
Both the Petzl and the Ushba 10mm glue-ins are rated to 25kN, so unless you're using the giant Petzl glue-ins (14mm, 50kN), they should be the same strength.
That picture sure looks weird. I can't imagine any scenario that would result in the bolt breaking deep in the hole with a bend, since it shouldn't be possible to break through the epoxy and the rock to that depth on a properly installed glue-in.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Thanks for clearing that up. I think it goes without saying that "properly placed" includes
placing the bolt in suitable rock, since crumbling rock is the only thing that makes sense.
But even then, I simply can't picture the bolt bending to that extent, that far from the eye,
knott to mention the bolt bending in the wrong direction. So again I ask, WTF?
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klk
Trad climber
cali
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Well, if the bolt as originally placed could pass visual inspection, one possible scenario is that the soft rock at the surface gradually eroded away as folks twisted and dangled on that bolt. (Thus providing the weird angle stresses that the op describes.) Then the snap line would represent that place where the rock was just good enough not to pulverize under that sort of stress. In that case, the bolt before it broke would've looked pretty manky-- a chossy, fracture scoop around the eye, some of the shaft probably visible. I have seen bolts that bad in serious choss.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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To my mind, if the bolt was properly oriented, the loop itself would be resting against the rock,
and even if the rock inside crumbled, the rock outside would support it and prevent bending.
That is why I suspect it was placed upside down, or in a manner so that it was opposite to the direction of loading.
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scuffy b
climber
Zeno's Paradise
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Placed in a roof, HK.
This explains the direction of bend.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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So how would the bolt be loaded if it was rotated 180 degrees?
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klk
Trad climber
cali
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Maybe I wasn't clear-- it was placed upward into a roof (unless I read incorrectly) made of complete choss. So when folks dangled and spun, the surface rock gradually broke and eroded away, exposing part of the shaft. The better rock didn't erode, thereby creating a fulcrum line right, which is where it sheared. One would have to have rock so crummy that you could crunch away the surface with not much more than a fingernail scraping at it, but from the quotes, it sounds like that's the scene there. I'm not crazy about this scenario, but can't think of a likelier one.
I am presuming here that, if it had been fixed with the eye that far stuck out from the original surface, that someone would've said something.
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dirtineye
Trad climber
the south
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Must.. See.. Cross section!!! (choke) (gasp)
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Brian in SLC
Social climber
Salt Lake City, UT
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Would really like to see a cross section straight on photo of the break.
My bet is that if it was repeatedly dogged on, and it was originally placed so that part of the shaft of the bolt was in contact with the rock (or it got that way when the rock busted around it), then it eventually got a scratch/dent on it which bloomed into a stress riser. Fatigue then fast fracture failure when the crack became big enough to not withstand the load.
Er something like that.
Anyhoo, a good close up photograph of the surface of the busted area would be super revealing.
-Brian in SLC
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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I will Paypal $10.00 (the cost of 2 beers with tip) to the first person who posts close-up
pics of the hole of the broken bolt (alternately, they can be e-mailed to me).
The eye of the bolt should have been resting against the rock in the direction of force,
preventing the bending shown in the pic. If pics are knott too much trouble, beers on me!
Edit: Brian - we were composing our posts at the same time - LOL!
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scuffy b
climber
Zeno's Paradise
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"So how would the bolt be loaded if it was rotated 180 degrees?"
It would be loaded the same.
The bend is a result of loading in pull, not shear.
The bolt was placed in a roof, not near a roof, not before or
after a roof.
The direction of the bend is OK. The location of the bend, so
far from the eye, indicates soft rock or crappy hole.
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bwancy1
Trad climber
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Let me fix that for you...
The direction of the bend is OK. The location of the bend, so
far from the eye, indicates soft rock or crappy hole"
That makes sense to me too...
...or not being set deep enough.
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JLP
Social climber
The internet
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There appear to be no witness marks anywhere on the bolt. Assuming the bolt was photo'd sometime reasonably soon after the break, I would assume the thing was sticking out of it's hole up to near the "glue ring"
It looks like it broke pretty close to the first "glue ring" feature. The bolt "cross section" will be thinner here - significantly less strong. Depending on how the ring feature was manufactured into the bolt, there will certainly be additional stresses, the magnitude of which depend on the process.
I'm therefore concerned about the glue ring.
Sigma = My/I, I = pi r^4/4. Let's say the ring is 5cm dx from the load point, so 1kN force fall is 50 N-m @ break. Let's call the ID of the ring @ 5mm, so r = .0025 m. Solving, we get Sigma = ~8E10 Pa, not accounting for the additional stress imposed by the "glue ring" geometry and manf. process, and additional likely torsional stresses. Titanium Alloy snaps at 9E9 Pa. My numbers are guesses, but they show that it is certainly possible. Have fun speculating - or stick the real #'s in and see what you get.
Don't really need to see much else in the pic, just dimensions of a similar bolt. Looks like a design/installation issue to me - both. Direction of loading shouldn't matter beyond inducing torsion - ie, doesn't matter if they placed it upside down - sideways might matter more.
Lesson to self: bolts sticking out of rock = bad - these glue ins are probably best with the ring pointing down, seated against the rock and into some of the epoxy that oozes out of the hole.
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healyje
Trad climber
Portland, Oregon
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Notice how most bolts of this variety are best installed in a recessed manner as opposed to just drilling a hole and sticking it in.
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Chiloe
Trad climber
Lee, NH
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Here's an Ushba titanium bolt, which looks more similar to the one that broke.
Mounted flush with the rock:
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Nor Cal
Trad climber
San Mateo
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Knott,
yes, a simple back-up would have prevented his accident. Sad part is he had two ropes hanging, he could have easily tied in shrot on the second. he grabbed the rope during his fall and this prevented his ushba from camming into place. The device was only attached to his belay loop. A device such as the mini traxion would not have needed to cam into place.
He and I each logged over 10k feet using the ushba, most of that was in the valley and at our local rock (where he got hurt) it was rare that we did not back it up and we have take many falls with the device. I figure that if he had further to fall he would have let go of the rope and the device would have caught him. I guess that is why it's an accident. one that should not have happened.
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neebee
Social climber
calif/texas
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hey there nor cal and all... say, this whole bolt stuff is very interesting... i was just sitting here taking it all in...
i am only posting, just to say to nor cal:
say, i hope your friend is doing well... my grandkids have a step mom, and her DAD was a roofer... he fell and landed on his feet and broke both feet too... long after, he has still had trouble and has never been able to work again---thus, it has been very hard on him.... sure hope your friend recovered well, and if not, sure hope some good will come his way...
*back to the bolt-stuff, you all... (i really DID enjoying listening to everyone take on it) ...
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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[Lord Slime asked me to post this for him; reminds me of the good ol' days of rec.climbing]
----------------------------------
Geez, I come home from climbing at Rifle to find this cluster-fuçk on my computer.
First of all, let me respond to all the morons who spew without a clue.
PUD: "Titanuim is brittle compared to mild steel"
You're a moron. In the future try to refrain from commenting on subjects you clearly know nothing about. You say you've seen Ti bolts break in your line of work, whatever that is. If they have, either you installed the wrong bolt for the job or there's an engineering mistake. (Probably the former.) This is true for ANY material, including steel btw, duh.
SOY CONCERNED: "Doesn't titanium make a more brittle metal than most stainless recipes for steel?"
See above.
DR. ROCK: "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."
Dr. Rock, you missed your calling as Press Secretary in the Bush Administration. Since you don't have a fuçking clue how the Tortugas are heat-treated, you spin this to be the problem. Geez, these guys are making nuclear submarines out of Ti, and they just FORGOT about heat treating? Moron.
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), that he doesn't like ANY Ushba products. That's cool Nor Cal, they don't like you either.
THE KID: "Here at the new river gorge, when we use glue in's they are petzl stainless steel units.. i would take stainless over ti any day."
Yeah, that's because you don't know shít. I've been to the New and seen for myself the corrosion on all those stainless steel bolts. Find the post by Greg Barnes where he describes stainless glue-ins breaking in Thailand. It'll take a little longer at the New, but it will certainly be within your lifetime, however short that turns out to be.
DIRTINEYE, STEVEP, Greg Barnes, JLP and a few others have their shít together, as does Hardman Knott, of course. (Greg, would you like an updated, much better article to replace Deepbluesea?)
Just looking at the photo of the bolt, it was clearly not seated all the way into the hole. There's no way the shaft could have been bent if it was fully seated. This is a common installer fuçk-up with glue-ins in steep rock, since the bolt must be held in place until the glue gels enough that the bolt doesn't creep out of the hole due to gravity. We used duct tape to hold them on severely overhanging placements, or sometimes I just held them for five minutes.
In addition, I agree with Hardman, the bolt seems to have been installed upside-down, since the bend is backwards to the normal pull they were designed for. When installed properly, with the eye aligned in the direction of pull, the eye will hit the rock, preventing further deformation.
Putting a plastic bend into a Tortuga is NOT easy. Perhaps someone clipped in directly and then fell onto the bolt. (?)
Someone said (it was hard to tell who) that the bolt was being torqued in use. Well, that'll break it if the torque is high and frequent enough. If the bolt is replaced, use the drill to create a groove for the eye to rest in (orient it properly!) and backfill around the eye with glue. This will prevent it from being torqued. And by the way, a steel glue-in will break too if you don't install it properly and torque the shít out of it. Duh.
Lastly, if the rock is really soft, a glue-in is the ONLY answer. But I'm wondering, is the rock there really wet? Is there corrosion on the stainless steel bolts (I'm assuming they're SS bolts.). Why was a Ti bolt chosen?
Who has the bolt? Send it to me and I'll get it to the original metallurgist/climber who designed it for failure analysis. Hardman can give you my email.
Lord Slime
P.S. I have clues for sale for those of you who (clearly) need them. Send $29.95 and a SASE to me for a set of five all-purpose clues. Limit five per moron.
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Dr. Rock
Ice climber
Castle Rock
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Why do morons like lightning?
They think someone is taking their picture.
Why did it take the moron an hour to eat breakfast?
Because the orange juice carton instructions said Concentrate!
What do you call 10 Morons standing ear to ear?
A wind tunnel.
How do you get a Moron on the roof?
Tell him the drinks are on the house.
* Use with 7/16" drill bit.
* Weight: 74 grams
* Dimensions: 10mm x 13 cm (3/8" x 5")
* Stength: 15kN
or
Shaft Length 80mm
Shaft Diameter 10mm
Weight 2.6 oz / 75g
Rated Strength 25 kN
Which one?
"Titanium was our first choice and after being turned away by several climbing equipment manufacturers we hooked up with Ushba Mountaineering. After our first meeting at the local pub, and several beers, we were sure this marriage was going to last.
We went through a meticulous design process before boiling it all down to the simplest solution. The new Ushba "Tortuga" bolts (Spanish for turtle) are simple "P" shaped welded cold-shuts made out of titanium. They are large enough to be used for both intermediate bolts and lowering anchors. They meet all existing UIAA standards for strength and will set new standards for anti-corrosion properties. (The UIAA has formed a special sub-committee to investigate marine bolt standards.)
We also had to think about the glue since the glue provides an important part of the overall solution. The glue isolates the bolt from any possible metals or chemical corrosives embedded in the rock and prevents water from wicking into small crevices next to the metal. It also has to withstand the marine environment in its own right! Here we gleefully took Sam Lightner's advice gained from years of gluing bolts in Thailand. The Hilti HIT C-100 appears to be your best bet. "
Just gathering information.
Are these stress cracks?
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Dr. Rock
Ice climber
Castle Rock
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Unalloyed titanium and all alpha titanium alloys are weldable. Although the alpha-beta alloy Ti-6Al-4V and other weakly beta-stabilised alloys are also weldable, strongly beta-stabilised alpha-beta alloys are embrittled by welding. Most beta alloys can be welded, but because aged welds in beta alloys can be quite brittle, heat treatment to strengthen the weld by age hardening should be used with caution.
Unalloyed titanium is generally available in several grades, ranging in purity from 98.5 to 99.5% Ti. These grades are strengthened by variations in oxygen, nitrogen, carbon, and iron. Strengthening by cold working is possible but is seldom used. All grades are usually welded in the annealed condition. Welding of cold-worked alloys anneals the heat-affected zone (HAZ) and eliminates the strength produced by cold working.
Alpha alloys Ti-5Al-2.5Sn, Ti-6Al-2Sn-4Zr-2Mo, Ti-5Al-5Sn-2Zr-2Mo, Ti-6Al-2Nb-1Ta-1Mo, and Ti-8Al-1Mo-1V are always welded in the annealed condition.
A1pha-beta alloys of Ti-6A1-4V can be welded in the annealed condition or in the solution-treated and partially aged condition, with ageing completed during postweld stress relieving. In contrast to unalloyed titanium and the alpha alloys, which can be strengthened only by cold work, the alpha-beta and beta alloys can be strengthened by heat treatment.
The low weld ductility of most alpha-beta alloys is caused by phase transformation in the weld zone or in the HAZ. Alpha-beta alloys can be welded autogeneously or with various filler metals. It is common to weld some of the lower alloyed materials with matching filler metals. Filler metal of an equivalent grade or one grade lower is used to ensure good weld strength and ductility. Filler metal of matching composition is used to weld the Ti-6Al-4V alloy. This extra low-interstitial (ELI) grade improves ductility and toughness.
The use of filler metals that improve ductility may not prevent embrittlement of the HAZ in susceptible alloys. In addition, low-alloy welds can be embrittled by hydride precipitation. However, with proper joint preparation, filler-metal storage, and shielding, hydride precipitation can be avoided.
Metastable beta alloys Ti-3Al-13V-11Cr, Ti-11.5Mo-6Zr-4.5Sn, Ti-8Mo-8V-2Fe-3Al, Ti-15V-3Cr-3Al-3Sn, and Ti-3Al-8V-6Cr-4Zr-4Mo are weldable in the annealed or solution heat treated condition. In the as-welded condition, welds are 1ow in strength but ductile. Beta alloy weldments are sometimes used in the as-welded condition. Welds in the Ti-3Al-13V-11Cr alloy embrittle more severely when age hardened. To obtain full strength, the metastable beta alloys are welded in the annealed condition; the weld is cold worked by planishing, and the weldment is then solution treated and aged. This procedure also obtains adequate ductility in the weld.
Welding processes
The following fusion-welding processes are used for joining titanium and titanium alloys:
* Gas-tungsten arc welding (GTAW)
* Gas-metal arc welding (GMAW)
* Plasma arc welding (PAW)
* Electron-beam welding (EBW)
* Laser-beam welding (LBW)
* Friction welding (FRW)
* Resistance welding (RW)
Fluxes cannot be used with these processes because they combine with titanium to cause brittleness and may reduce corrosion resistance. The welding processes that use fluxes are electroslag welding, submerged arc welding, and flux-cored arc welding. These processes have been used on a limited basis. However, they are not considered to be economical because they require high-cost, fluoride-base fluxes.
Gas-tungsten arc welding is the most widely used process for joining titanium and titanium alloys except for parts with thick sections. Square-groove butt joints can be welded without filler metal in base metals up to 2.5 mm thick. For thicker base metals, the joint should be grooved, and filler metal is required. The heated weld metal in the weld zone must be shielded from the atmosphere to prevent contamination with oxygen, nitrogen, and carbon, which will degrade the weldment ductility.
Gas-metal arc welding is used to join titanium and titanium alloys more than 3 mm thick. It is applied using pulsed current or the spray mode and is less costly than GTAW, especially when the base metal thickness is greater than 13 mm.
Plasma arc welding is also applicable to joining titanium and titanium alloys. It is faster than GTAW and can be used on thicker sections, such as one-pass welding of plate up to 13 mm thick, using keyhole techniques.
Electron-beam welding is used in the aircraft and aerospace industries for producing high-quality welds in titanium and titanium alloy plates ranging from 6 mm to more than 76 mm thick. Because the welding is performed in a high-vacuum atmosphere, low contamination of the weldment is achieved.
Laser-beam welding is increasingly being used to join titanium and titanium alloys. Square-butt weld joint configurations can be used, and the welding process does not require the use of vacuum chambers; gas shielding is still required. This process is more limited than electron-beam welding regarding base metal thickness, which cannot usually exceed 13 mm.
Friction welding is useful in joining tube, pipe, or rods, where joint cleanliness can be achieved without shielding.
Resistance welding is used to join titanium and titanium alloy sheet by either spot welds or continuous seam welds. The process is also used for welding titanium sheet to dissimilar metals, that is, cladding titanium to carbon or stainless steel plate.
Filler material and electrodes
Filler-metal composition is usually matched to the grade of titanium being welded. For improved joint ductility in welding the higher strength grades of unalloyed titanium, filler metal of yield strength lower than that of the base metal is occasionally used. Because of the dilution that occurs during welding, the weld deposit acquires the required strength. Unalloyed filler metal is sometimes used to weld Ti-5A1-2.5Sn and Ti-6A1-4V for improved joint ductility.
The use of unalloyed filler metals 1owers the beta content of the weldment, thereby reducing the extent of the transformation that occurs and improving ductility. Engineering approval, however, is recommended when using pure filler metal to ensure that the weld meets strength requirements.
Another option is filler metal containing lower interstitial content (oxygen, hydrogen, nitrogen, and carbon) or alloying contents that are lower than the base metal being used. The use of filler metals that improve ductility does not preclude embrittlement of the HAZ in susceptible alloys. In addition, low-alloy welds may enhance the possibility of hydrogen embrittlement.
Shielding gases in welding titanium and titanium alloys are only argon and helium, and occasionally ? mixture of these two gases is used for shielding. Because it is more readily available and less costly, argon is more widely used.
Electrodes. The conventional thoriated tungsten types of electrodes (EWTh-1 or EWTh-2) are used for GTAW of titanium. Electrode size is governed by the smallest diameter able to carry the welding current. To improve arc initiation and control the spread of the arc, the electrode should be ground to a point. The electrode may extend one and a half times the size of the diameter beyond the end of the nozzle.
Bottom Line:
I will bet you dollars to donuts that we see a recall of these bolts.
The welding and heat treating were not done right.
My 2 cents.
"We designed it in a pub after everybody else told us we were nuts..."
That should be your first warning signal, right there.
Your Witness.
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Nor Cal
Trad climber
San Mateo
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thanks Knott, I like being called an idiot you made my day. But I see that I'm not the only one you are calling names, does this make you feel tough? Does it make you right?
And since you speak for Ushba tell them that I am glad that they don't like me.
You say that the Ushba (or any ascender) is not to be used for this application and you have used it your self for the same thing. Huh?
The Ushba can be used for solo top rope:
http://www.mtntools.com/cat/rclimb/ascend/ushbabasicascender.htm
A quote from Mtn Tools page:
For solo top rope practice, anchor your rope directly above your intended climbing route, attach the BASIC to the rope and clip directly to your harness' belay loop - with a symmetrical locking biner (oval or rounded pear). Be sure to a tie back up jam-knot once you are off the ground and also every few feet there after. Your BASIC will follow your every move closely - and you'll be able to climb more naturally with both hands on the rock.
neebee, thanks. This happened three years ago and he is doing fine.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Nor Cal - I assume you missed this part?
[Lord Slime asked me to post this for him; reminds me of the good ol' days of rec.climbing]
------------------------------------------
[snip quoted text from Lord Slime]
------------------------------------------
Also, did you notice this sentence from the paragraph you quoted?
Be sure to a tie back up jam-knot once you are off the ground and also every few feet there after.
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Chiloe
Trad climber
Lee, NH
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HK did clearly note that he was channeling Lord Slime, who also signed his note.
Dr. Rock forgot to mention that his entire post was copyrighted material taken from someone else.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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I was wondering why there wasn't a link provided for his cut 'n paste job...
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bwancy1
Trad climber
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For Chrissakes!
The bolt was placed under a roof, vertically, facing downwards.
All this "When installed properly, with the eye aligned in the direction of pull, the eye will hit the rock, preventing further deformation" is killing me.
Get it straight, the thing was installed vertically.
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Brian in SLC
Social climber
Salt Lake City, UT
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I was wondering why there wasn't a link provided for his cut 'n paste job...
I'm more wondering why you're Lord Slime's internet bitch...
Ha!
Does that mean you get the flames intended for him, then?
Same offer from me to have a metallurgist look at the busted Tortuga. I'd pay postage, both ways.
Cheers,
-Brian in SLC
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Nor Cal
Trad climber
San Mateo
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Knott, yeah I missed that part. I'm at work and have little time to read in detail. my friend should have been backed up. I thought I mentioned that earlier
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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bwancy1 - I would like to knott only see close-up photos of the area where the bolt broke,
but also an overview showing the angle of the rock where the bolt was installed. So are you
saying it's dead horizontal? If knott, then what angle? And why wasn't the eye of the
bolt being supported by the rock? A picture really is worth a thousand words (and then some)...
FWIW, a few of these same bolts we installed at Mickey's Beach reside in roofs,
and have been dogged the shít out of since 2002. The bolts were placed in a manner
so that when loaded, the eye would get pushed against the rock. Also, as Lord Slime
mentioned, they were completely flush with the rock, which sometimes necessitated
holding the bolt in place during the 5 minute curing process.
Brian - I think you need clarification on what an Internet Bitch™ is...
An Internet Bitch™ is someone like Crowley, Rimjob, or Ouch, who stalk others
through various threads posting unsolicited incitements in repetitive fashion.
I was merely acting as a messenger for His Lordship. Don't shoot the messenger!
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bwancy1
Trad climber
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HK Wrote So are you saying it's dead horizontal?
NO!! VERTICAL!! As in, the shaft of the bolt was (edit...almost) parallel to a line passing through the center of the earth, and perpindicular to a line tangent to the surface of the earth at that point. As in vertical, installed under a roof, in a ceiling, pointing down.
Ok, truth is I have no idea how it was installed. This is just my understanding based on the descriptions given by the OP etc.
Carry on.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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I meant: was the ROOF horizontal...
So it sounds like is was.
Eagerly awaiting the photos - anyone thirsty?
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Chiloe
Trad climber
Lee, NH
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Ok, truth is I have no idea how it was installed.
A number of posts have said it was installed vertically (HK's "horizontal" referred to the rock surface, I think -- give him some credit) and/or that it broke in tension, not in shear.
But what's bothering me and I think some others here is that the photo shows a bolt that broke where it was bending backwards, as if forced in that direction with about 1/3 of its length unsupported. That bend doesn't seem to fit with the idea of breaking purely in tension, or by a straight downwards pull on a vertically-placed bolt. It looks more like the bolt was feeling shear forces, and with a whole lot of leverage. But that's just a guess from looking at the one photo we've seen.
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dirtineye
Trad climber
the south
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Look, you can't assume that the bend happened during the breaking. Maybe it did, but you can't tell from that picture.
Until you see the cross section, and preferably also know just how the bolt was situated before it broke, more argument is pointless.
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Chiloe
Trad climber
Lee, NH
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Looks like it broke, after bending, at or near the first glue groove.
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Dr. Rock
Ice climber
Castle Rock
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Sorry for the lack of quote marks.
I thought it would be obvious that it was not my work.
Next time, quotes.
Those jokes are older than Half Dome, I do believe.
Bottom Line:
That is a critical location, an overhang.
Use something that won't break.
We could sort this out for days, with charts and graphs and formulas and attorneys and pictures and x rays, but that is not the point.
The point is, we should not be having this discussion in the first place.
A big hefty steel bolt in there, and this does not happen.
A placement this critical requires something that is 1000 times as strong as the load, that way, you can mis install it, twist on it, swing on it like Tarzan, and it will not even come close to breaking, get it?
Save the Titanium for the frickin Space Shuttle for Chrisasakes!
This is serious business, Gravity, the Big G.
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Chiloe
Trad climber
Lee, NH
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Next time, quotes;
And credit to the author?
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Dr. Rock
Ice climber
Castle Rock
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It was a college abstract, not a publication.
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Brian in SLC
Social climber
Salt Lake City, UT
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Looks like it broke, after bending, at or near the first glue groove.
Sure does. Which makes sense.
Depending on how they get the grooves in the bolt, that might be a contributor too (ignoring that the bolt shouldn't see much load in that area though).
I seem to recall, early in my climbing career, deciding that putting a few extra teeth in an ice tool pick seemed a good idear. Used a triangle file. Wasn't long before that pick snapped right at the new tooth area.
The Tortugas I've looked at (Liberty here in SLC is/was the distributor) all seemed finished pretty nicely in the groove area (don't recall any sharp inside corners).
-Brian in SLC
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Chiloe
Trad climber
Lee, NH
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A big hefty steel bolt in there, and this does not happen.
You sound so certain.
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Dr. Rock
Ice climber
Castle Rock
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You mean like scoring a glass rod before you snap it, of course.
I just opened up a Climbing Company.
We make Berrilium Quick Draws.
The feature Boron keepers.
Super light.
Hang off them all day.
Any takers?
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Ain't no flatlander
climber
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A bad placement is a bad placement. The metal doesn't matter when the user screws up.
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mewalrus
Trad climber
Minneapolis, MN
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"The bolt was placed under a roof, vertically, facing downwards. "
Well looking at the ushuba bolt its obvious that the design is not optimal for vertical placement as vertical placement will create torque when the bolt is fallen on, the offset eye causes this where as, in a horizontal placement it prevents torque.
I would say its not appropriate to use these offset bolts in a dead vertical placement.
" A bad placement is a bad placement. The metal doesn't matter when the user screws up."
A bolt not designed for the loading direction it receives will matter, the metal won't necessarily matter.
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couchmaster
climber
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Has anyone contacted Ushba yet? They have lots of Ti bolts out there in the world, it's a product considered superior to all others.
Edit, to those who think that the placement was wrong, think about that for a moment, there's no way in hell a bolt/hanger is as good as this combo should be in that application.
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mewalrus
Trad climber
Minneapolis, MN
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A symmetrical stainless steel glue in should be used in this application.
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stevep
Boulder climber
Salt Lake, UT
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Dr. R, you're being a little too sure of yourself. There's not that much difference in strength between Ti and steel bolts. As for a weld-related failure, I'd expect that to be much closer to the weld.
But basically there are too many variables to judge. If we assume that the bend and the break are related (likely but not definite), then either the bolt was installed sticking too far out allowing the bend and failure, or it was set deep, but not enough glue was used and the rock around it crumbled, allowing the same type of failure as if it had been placed sticking too far out. In either case, a steel bolt would not necessarily have been much better.
If the failure was a combination of force-related stresses and some sort of chemical weakening, then most likely the Ti bolt would have lasted longer.
If it just happened to be one bolt with a flaw, well, sh!t happens. Even 6 Sigma standards don't mean there are never flaws.
We'll know none of this without an inspection of the bolt and some more detailed information on what the placement looked like before the break.
At any rate, there's alot of these things out there, and based solely on that bend, I'd be pretty surprised if this represented anything that would cause a recall. So I'd take your dollars to donuts bet. Your $12 to my 12pack of donuts?
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Ain't no flatlander wrote:
A bad placement is a bad placement. The metal doesn't matter when the user screws up.
This quote should be put up somewhere as a big flashing neon sign.
It was a bad placement.
Deal with it...
Edit: I will Paypal $100.00 to the first person who offers verifiable photographic
proof that that bolt was placed with the eye flush with the rock, and in a way that
the main forces to the bolt are consistent with the way for which is was designed.
I'm willing to put my money where my mouth is. Where, oh where are the pics?????
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graniteclimber
Trad climber
Nowhere
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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), that he doesn't like ANY Ushba products. That's cool Nor Cal, they don't like you either."
Ushba marketing copy (on any number of web sites): "Compact, lightweight, and easy to use, the Basic Ascender is rope-friendly, extremely strong, and will not slip on icy or muddy ropes. These fail-safe features combine to make it an excellent choice for top-rope solo and self-belay applications.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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It's idiotic to Solo TR with no back up. End of story.
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Darryl Cramer
Social climber
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I acquired a bunch of the Tortuga anchors to use in sandstone and seaside cliffs in WA. I placed one in a boulder in my front yard and beat the heck out of it with a sledge hammer – I couldn’t get it to break.
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Dr. Rock
Ice climber
Castle Rock
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They take out the Titanium pedal spindles and brake binder bolts most of the time when building road bikes.
Some people even change out chain ring bolts.
Snappy Gator, that Ti stuff.
It took me 5 minutes on Google to come up with that welding article.
Just type in
"Titanium" + "welding" + "brittle" etc and you will get a plethora of information.
I would put that failed bolt in a Safe Deposit Box until you figure out which barrister to retain.
If I were an Attorney, I would be all over this, salivating at the chops.
If the route sees heavy traffic, go for The Beef.
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JLP
Social climber
The internet
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This is turning into a retard fest.
If you have to surf Google to bring your knowledge up to the point where you feel like you can post something relevant - you probably can't.
Ti by itself is rather weak. The alloys are pretty strong. SS comes in many flavors as well. Some are stronger than some of the Ti alloys, some not.
The break didn't happen anywhere near the weld.
Bolts break all the time for various reasons, so you should consider that when you are out climbing.
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Forest
Trad climber
Tucson, AZ
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They take out the Titanium pedal spindles and brake binder bolts most of the time when building road bikes.
Some people even change out chain ring bolts.
??? um, is there a typo in there somewhere? What do you mean "they take out"?
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Dr. Rock
Ice climber
Castle Rock
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Again, it does not matter if there was a little slack hanging out.
You want a hanger that you can mis install and bend back and forth til hell freezes over without breaking.
Build stuff for the masses, expect the worse, and your product will survive.
You need a fudge factor.
Titaniun has no fudge factor.
It must be welded perfectly or else.
Easy to get a bunch of 3/8 inch round stock of various alloys.
Put it in a vice and bend it back and forth til it breaks.
Count the cycles.
It seems that Lord Slime is also the guy who designed this?
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Dr. Rock
Ice climber
Castle Rock
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Just some welding info.
I do not know if these were tig welded or not.
Could be a machine weld.
The weld looks real good, no under cutting, and no grinding needed.
Can't look at the HAZ (Heat Affected Zone) because of the black oxide, which is normal.
Ti dust is used in fireworks, interesting.
Anyway:
David Hoss wrote this for The Metal Fab Type Of Guy:
"Weld Preparation
Weld preparation should include removing any oil, grease, dirt, or grinding dust from the surfaces to be joined. Steam cleaning or an alkali dip in a dilute solution of sodium hydroxide can remove most of these contaminants. To remove the last remaining organic compounds just before welding, use a lint-free glove and methyl alcohol, acetone, or other chlorine-free solvent. Because most of these solvents have a low flash point, be sure they have fully evaporated before striking an arc.
On the most critical parts, using a small hot-air blower (hair dryer-style) to warm the part slightly ensures no moisture has condensed on the surface to be welded. Don’t overlook the fact that rubber gloves may contain chlorine as part of a vulcanizing process. Plastic gloves are recommended.
Pure Argon Applied Correctly
The argon must be 99.999 percent pure. Even if the argon is as pure as the 50 parts-per-million (PPM) range (99.995 percent), some yellow-straw discoloration can result. Many shops strive to maintain a 10-PPM contamination level during welding. If the color begins to mottle, or if it exhibits any hint of blue, the argon isn’t pure enough, or you’re not applying it correctly. Start the argon gas flowing for several seconds before using the high-frequency start. If you have enough shielding and the argon is being dispersed evenly over the part, you should see a uniform color.
Mottled or swirl patterns usually indicate too much argon is flowing (see Figure 1 ). Argon’s density is greater than air, so it tends to flow over the surface of a part in the same way water does. Where eddies occur, air can become mixed with the argon cover gas and create swirl patterns.
Figure 1
What really separates titanium welding from most other types of GTAW is the need for an argon cover on the weld’s back side. Wherever the titanium is heated, brittle alpha-case can form. For very complex parts with interior passages or parts that require a lot of welding repairs, glove boxes may offer an economical answer. For parts too large to fit through the glove box, special flexible polyethylene plastic bags, complete with attached gloves, can be used. Use a purge monitor to see when the bag contains clean-enough argon, strike an arc, and weld away. Working in airtight gloves, especially for extended periods, can be hot, but doing so is part of the challenge of working with titanium.
Finishing Up
The end of the weld is equally important. The titanium is hot, and the protective argon flow is still needed until the metal has cooled below about 500 degrees F. Color can be your best indicator of sufficient argon use. Some discoloration may occur beyond the HAZ and, depending on the criticalness of the weld, may be acceptable."
Here is some Heat Treatment info from TIMET:
"Heat Treating Titanium
Heat treatment of titanium fabrications is not normally necessary. Annealing may be necessary following severe cold work if restoration of ductility or improved machinability are desired. A stress relief treatment is sometimes employed following severe forming or welding to avoid cracking or distortion due to high residual stresses, or to improve fatigue resistance. Cleanliness of titanium parts to be heat treated is important because of the sensitivity of titanium to contamination at elevated temperatures. Titanium fabrications should be cleaned carefully prior to heating, using nonchlorinated solvents or a detergent wash, followed by a thorough water rinse. Handling following cleaning should be minimized to avoid potential surface contamination.
Most titanium grades are typically stress-relieved at about 1000°F (538°C) for 45 minutes and annealed at 1300°F (704°C) for two hours. A slightly higher stress relief temperature [1100°F (593°C), 2 hrs.] and annealing temperature [1450°F (788°C), 4 hrs.] are appropriate for the Grade 5 alloy. Air cooling is generally acceptable.
Although no special furnace equipment or protective atmosphere is required for titanium, a slightly oxidizing atmosphere is recommended to prevent pickup of hydrogen. Direct flame impingement for extended periods, leading to temperatures in excess of 1200°F (649°C), should be avoided because of the potential for contamination and embrittlement. Hydrogen or cracked ammonia atmospheres, also, should never be used, because their use would lead to excessive hydrogen pick-up, and embrittlement.
If a scale removal treatment, following a high temperature (1200°F; 649°C) anneal is not feasible, a vacuum or inert gas (dry argon or helium) atmosphere is recommended. Superficial surface discoloration, caused by annealing below 1200°F (649°C), may be removed by acid pickling in a 35% nitric acid – 5% hydrofluoric acid bath at 125°F (52°C). However, if long heating times or temperatures above 1200°F (649°C) have been used, a molten caustic bath or mechanical descaling treatment, followed by nitrichydrofluoric acid pickling, is necessary to remove scale."
You can pickle the stuff also.
More stuff from "Kenneth" at the Aerospace Engineers Forum:
"Cold reduction before after solution treating and before aging is not required for 6Al-4V Ti bolt material to achieve 160 ksi UTS. Typical aerospace bolt fabrication practice is to buy annealed material and to solution treat and age "blanks" in-house (after head forming/forging) to 160 ksi. The specifications they procure the material to require "heat treat capability" testing/certification of a sample of the as-shipped raw material after solution treament and aging (with no intermediate cold reduction) to the applicable tensile requirments.
I (like Wil) would be very, very cautious about the toughness of 6AL-4V Ti "pushed" to 180 k"
I bet the guy who wrote this gets a lot of dates:
" Abstract
Nanostructured Ti (100 -300 nm average grain size), processed by severe plastic deformation through equal channel angular pressing of commercially pure Ti rods after quasi-static compression (at 0.0004 s^{-1}strain-rate) of prismatic (2×2×7mm) samples has at low temperatures (77 and 4,2K) yield stresses two times larger than the initial CP-Ti, failure stresses ranging from 1.4 to 2.4 GPa. The shear failure phenomenon has been observed at 77 and 4,2K. Nanostructured Ti is absolutely thermomechanically unstable against catastrophic plastic shear under low temperature straining. The catastrophic plastic shear spreads through the whole section of the sample with a velocity close to the transverse sound velocity and has a dynamical character. It is supposed that the micro mechanism of the shear failure of nanostructured Ti consists in extending of the catastrophic shear by grain boundary dislocations. "
"EXECUTIVE SUMMARY
Hard alpha or high interstitial defects (HID) often, and erroneously, referred to as low-density
inclusions (type I) in titanium alloys, have been the focus of attention off and on since the
application of titanium to rotating components in gas turbine aeroengines. There have been
failures of components and, unfortunately, some loss of life associated with the presence of such
defects and a concomitant-reduced fatigue life. The early characterization of this class of defects
resulted in identifying a few key characteristics that are responsible for the reduced fatigue life of
titanium components that contain them. Chief amongst these characteristics is a higher hardness
than the nominal alloy due to interstitial (nitrogen, carbon, and oxygen) alloying at levels much
higher than the nominal alloy. Besides being hard and brittle, these nuggets of high interstitial
stabilization are refractory, relative to the melting temperature for the host titanium alloy, and are
slow to dissolve. This refractory nature, combined with the size of the initial seed, may permit
the nugget to survive, with its hardness characteristics, all the vacuum arc remelting (VAR)
process steps normally used to create a titanium ingot. This realization resulted in the institution
of triple VAR to replace the standard double VAR for premium-grade applications, resulting in a
significant reduction in occurrence of hard alpha defects."
Close Analogs: 4 other heat treatments of this alloy are listed in MatWeb.
Key Words: Ti-6-4; UNS R56400; ASTM Grade 5 titanium; UNS R56401 (ELI); Ti6Al4V, biomaterials, biomedical implants, biocompatibility
Component Wt. %
Al 6
Fe Max 0.25
O Max 0.2
Ti 90
V 4
Material Notes:
Information provided by Allvac and the references. Annealing Temperature 700-785ºC. Alpha-Beta Alloy.
Applications: Blades, discs, rings, airframes, fasteners, components. Vessels, cases, hubs, forgings. Biomedical implants.
Biocompatibility: Excellent, especially when direct contact with tissue or bone is required. Ti-6Al-4V's poor shear strength makes it undesirable for bone screws or plates. It also has poor surface wear properties and tends to seize when in sliding contact with itself and other metals. Surface treatments such as nitriding and oxidizing can improve the surface wear properties.
Physical Properties Metric English Comments
Density 4.43 g/cc 0.16 lb/in³
Mechanical Properties
Hardness, Brinell 334 334 Estimated from Rockwell C.
Hardness, Knoop 363 363 Estimated from Rockwell C.
Hardness, Rockwell C 36 36
Hardness, Vickers 349 349 Estimated from Rockwell C.
Tensile Strength, Ultimate 950 MPa 138000 psi
Tensile Strength, Yield 880 MPa 128000 psi
Elongation at Break 14 % 14 %
Reduction of Area 36 % 36 %
Modulus of Elasticity 113.8 GPa 16500 ksi
Compressive Yield Strength 970 MPa 141000 psi
Notched Tensile Strength 1450 MPa 210000 psi Kt (stress concentration factor) = 6.7
Ultimate Bearing Strength 1860 MPa 270000 psi e/D = 2
Bearing Yield Strength 1480 MPa 215000 psi e/D = 2
Poisson's Ratio 0.342 0.342
Charpy Impact 17 J 12.5 ft-lb V-notch
Fatigue Strength 240 MPa 34800 psi at 1E+7 cycles. Kt (stress concentration factor) = 3.3
Fatigue Strength 510 MPa 74000 psi Unnotched 10,000,000 Cycles
Fracture Toughness 75 MPa-m½ 68.3 ksi-in½
Shear Modulus 44 GPa 6380 ksi
Shear Strength 550 MPa 79800 psi Ultimate shear strength
Electrical Properties
Electrical Resistivity 0.000178 ohm-cm 0.000178 ohm-cm
Magnetic Permeability 1.00005 1.00005 at 1.6kA/m
Magnetic Susceptibility 3.3e-006 3.3e-006 cgs/g
Thermal Properties
CTE, linear 20°C 8.6 µm/m-°C 4.78 µin/in-°F 20-100ºC
CTE, linear 250°C 9.2 µm/m-°C 5.11 µin/in-°F Average over the range 20-315ºC
CTE, linear 500°C 9.7 µm/m-°C 5.39 µin/in-°F Average over the range 20-650ºC
Specific Heat Capacity 0.5263 J/g-°C 0.126 BTU/lb-°F
Thermal Conductivity 6.7 W/m-K 46.5 BTU-in/hr-ft²-°F
Melting Point 1604 - 1660 °C 2920 - 3020 °F
Solidus 1604 °C 2920 °F
Liquidus 1660 °C 3020 °F
Beta Transus 980 °C 1800 °F
So would you rather worry about all of that gobbledeegoop while your climbing, or go Bomber?
References for this datasheet.
http://asm.matweb.com/search/SpecificMaterial.asp?bassnum=MTP641
Looks like it's hangin out a bit.
Maybe they need to change the pic over at USHBA?
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tradmanclimbs
Ice climber
Pomfert VT
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I would totally bitch about the placement in that add if i ran accross it climbing, " dumb bastards didn't counter sink it"
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BKW
Mountain climber
Central Texas
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Topic Author's Reply - Aug 6, 2008 - 08:41am PT
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OK Hardman here is your cross section photo
I'll be in TM this weekend and we can settle then
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pud
climber
Sportbikeville
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California State Certified Structural Welder.
State Fire Marshall liscensed Pyrotechnic Operator.
Journeyman Machinist Local 44
Titanuim is brittle compared to mild steel.
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dirtineye
Trad climber
the south
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Something looks fishy there. The only bright metal is at the upper edge, probably where the break started. OR POSSIBLY FINISHED
The rest looks funny.
From the climbing pic, it looks for all the world like there is another bold just over the roof and the guy is clipping it in the pic.
Getting out to the edge of a roof like that to make a clip or even a placement with such a good right hand hold and a place for both feet on the back wall is easy.
That loads of people clip that thing under the roof and hangdog it just shows to go you that sport climbers are idiots.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Thanks for posting that link. I had to register on that site in order to see this pic along
with the 3 super hi-rez pics of the broken bolt. Is it possible to get a higher rez version
of this pic? I assume it was taken with at least a 5 megapixel camera?
It appears that the bolt is placed at a 45 degree angle, but it's hard to tell from the distance.
I zoomed in on it in Photoshop, but it's knott conclusive. {Edit: I just looked again,
and I would say it actually IS pretty conclusive. It certainly does look to be set
at a 45 degree angle in relation to the surface of the rock}. The bolt does appear
to be protruding from the rock somewhat...
BKW - my offer of two beers was for the bolt-hole (and ideally a wide view as well), knott head of the broken bolt.
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Dr. Rock
Ice climber
Castle Rock
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BKW, do you have your receipt?
Or did somebody else buy it?
Do you know if they have a receipt?
What kind of rock is this?
Do you have GPS specs?
I want to look at a geological map while I am going through the stacks on Titanium.
One thing puzzles me.
Why did the bolt break before the host rock came loose?
I thought this was loose rock?
Maybe all the glue sat at one point at the bottom, a fulcrum point so to speak.
This would leave the shaft loose at the top, allowing the bolt to pivot, but still hold.
Or, maybe somebody completely twisted that bolt a couple of times.
This poor guy weighs 210 lbs, so if he were hanging there spinning, he could put enough torque on that part to twist it?
Cool pic.
Looks crystalized with a an external hardness thing done.
Or that's just Titanium Oxide on the outside.
If you have the receipt, then they can trace this back to the Billet or Extrusion used to make this part.
If they got a bad batch of Ti, there miught be other bolts out there ready to snap.
Finding them might be problematic.
Until then, don't clip into anything that looks like TiO2.
Holy Cow this thing looks like it was installed almost horizontally:
I would ask you to go back up and get one of those hi-rez shots of the other half, but we do not need any more drama from that are for at least ten years, thanks.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Here are a couple e-mails I got yesterday - enjoy!
From: John Byrnes
Date: August 5, 2008 11:53:24 AM PDT
To: Dave Buchanan
Subject: Another post
Hey Dr. Rock, how subtle of you to juxtapose a skull and crossbones with a photo of a Tortuga. Take a look at Chiloe's photo of a stainless bolt next to a Tortuga (just one of many he's posted on Supertopo). But of course, you're too stupid to figure that out, so let me advise you. Go to Thailand or Cayman Brac and go climbing. Just don't clip any of the Tortugas. Be sure to have your belayer stand to the side.
Thank you for posting a lot of information about Titanium that you don't understand in a lame attempt to salvage some dignity for your moronic heat-treatment post. As if cutting-and-pasting makes you an expert in metallurgy. Or that you can diagnose cracks in the bolt from a low-res photograph. Or better, Photoshop cracks in.
You think Tortugas will be recalled and you're betting donuts? Or is it dollars? How many? How much IS a dozen of donuts these days?
And finally, your ignorance is stamped "Official" with your complete lack of understanding of how new products are born. They called the Wright Brothers "nuts". That guy Ford is nuts! He's trying to build a $500 automobile that everyone can afford. Bell was nuts too, because who would ever want that thing called a telephone? Having personally been involved in the development of five first-of-their-kind products, I know that when someone calls you nuts it means you've got a really good idea. Good luck Dr. Rock, you need it.
Lord Slime
From: John Byrnes
Date: August 5, 2008 3:27:33 PM PDT
To: Dave Buchanan
Subject: Re: Titanium Bolt Failure. :: SuperTopo Rock Climbing Discussion Topic
That Dr. Rock guy is such a tool. I pegged him perfectly the first time: Bush Admin.
Like George W., he has absolutely no evidence, not even satellite photos of semi-trailers or long aluminum tubes. He doesn't know shít about manufacturing processes. He probably has never held a Ti part of any kind in his hand. Yet, he's convinced he's right and he's selling fear (the skull & crossbones) to support his "conclusion".
It's idiots like this that convinced me to leave the first time, and confirm that I made the right choice. If someone comes up with the bolt, contact me. Barring that, I'm outta here. I'm not getting paid to watch the children in the daycare center.
John, you can post that.
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bwancy1
Trad climber
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Mystery solved.
Bolt installed at 45 degree angle and protruding from the rock. Not the way it was designed to be used.
For me, this explains the bending and the failure. I will continue to try to assess bolts that I clip when I am out climbing.
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Dr. Rock
Ice climber
Castle Rock
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There are bolts that would survive that faulty install.
That's my main point.
Do not count on everybody who installs the bolt to be a Rocket Scientist.
Mr. Slime, where do you guys have these built?
Just curious.
Who supplies the Ti?
Obviously, when you make anything out of Ti, you get to automatically tie it in with the Aerospace industry, the FAA, the 5,289,887,888,887 QC companies,gives the product more props.
Hardman, do you know if Mr. Slime wanted you to post those?
If I were a Professional Engineer, and I wanted people to have faith in my products, I sure the hell would not want people to see stuff like that.
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couchmaster
climber
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Yup, possibly solved, install and lots of load cycles as noted above. Coat hanger. Snap.
Yet still.....?
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Dr. Schlock wrote:
There are bolts that would survive that faulty install.
Name them...
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dirtineye
Trad climber
the south
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Infamous quotes from Dr Rock (Who sounds a lot like Drkodos)
"Until then, don't clip into anything that looks like TiO2."
"Again, it does not matter if there was a little slack hanging out."
HAHAHAHA, Oh, I see, installing something improperly has no bearing on its performance? Brilliant. I guess you think it does not matter if you only put one side of your double rap line in the device and though the biner then.
"You want a hanger that you can mis install and bend back and forth til hell freezes over without breaking. "
You might want that, but wish in one hand and sh!t in the other and see which one fills up first. There is no such hanger. GO google metal fatigue and learn why, but don't post endless crap here about it.
Incidentally, I'll be happy to wager that any current climbing stud or bolt installed in the same way will bend and then break. Most will probably break sooner in fact.
"Titaniun has no fudge factor."
Yes, there is no fudge in Ti alloys. Fudge is made of sugar, butter, flour and chocolate, and there is no metal in it really. If you want fudge, go to a fudge factory, or make it yourself from a bos you can get at the grocery store.
Apparently Lord Slime is correct in his assessment of DrRock.
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Brian in SLC
Social climber
Salt Lake City, UT
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Something looks fishy there. The only bright metal is at the upper edge, probably where the break started. OR POSSIBLY FINISHED
The rest looks funny.
That bright shiny spot is probably where the crack initiated and was present for some time, as evidenced by the shiny surface, indicating polishing over time, from repeated loading (ie, dogging).
Then, as the crack grew, it reached its critical flaw size and the bolt fast fractured. I think the mottled surface shows that fairly well, although a bit more high res. photo would show the direction of the failure a little better methinks.
So, looks like a typical failure. Could have initiated from a very small scratch in the surface of the bolt, or some such?
I'd be interested to see where the shiny crack was in relation to the direction of the eye (hard to tell from the pictures). Looks slightly out of line with the plane of the bolt eye. Looks like its on top of the bolt, just slight off to the side a few degrees?
-Brian in SLC
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Ain't no flatlander
climber
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If you're dumb enough to trust your life to a bolt that is very obviously placed badly, you should stay in the gym. That thing was crap no matter if it was steel, ti, or unobtanium.
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Dr. Rock
Ice climber
Castle Rock
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Hey, wait a minute, whats the difference between that install and a bolt placed in a vertical wall?
The loading is the same, be it a fall, or a static load, which, BTW, really freaks me out.
This thing did not snap during a fall, folks, it snapped while a guy was just hanging there!
Much less of a shock to the part in question.
There is an old saying in the ME world, if it don't bend, it breaks.
Look at the wings of a 747.
They flex 30 feet.
This thing did not flex much.
I have bent coat hangers that have taken more stress than that thing.
They got a little hot, but WTF, over?
Makes great welding rod.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Dr. Schlock - name the suitable bolts for that install job, troll...
Dirtineye wrote:
Infamous quotes from Dr Rock (Who sounds a lot like Drkodos)
LOL! I was thinking the same thing. Is the good doctor back?
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dirtineye
Trad climber
the south
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Brian, I am not so sure about that.
It is possible that the shiny bit is the last thing that failed.
if it is on the compressed side of the bend , then this is almost certainly the case. If it is on the other side, then yes it probably failed first.
BUT, the odd color of the granulated stuff in the break really bothers me.
Incidentally, I agree that the bolt was installed at too great an angle, and not with the rign embedded, BUT, you probably should not drill straight up for a gluein, cause all that is holding in that bolt is the glue.
I think I have seen something in the past about NOT using glueins for this sort of application for that very reason.
Think about it. You have a smooth hole. You fill it with glue and stick a shaft in it. The Glue and the glue alone is going to deal with every downward force ever put on that bolt, and this is NOT the case in a normal gluein scenario, where the glue just holds the bolt still and the rock and the bolt do all the work.
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Dr. Rock
Ice climber
Castle Rock
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You guys, I am 53, way too old to get personal.
Sorry I am no fun in that aspect.
Besides, I do not want anybody to cut my rope.
Wait a minute, I don't use a rope.
Why?
This thread is one reason.
If I am going to die, I want it to be my fault, not some minimum wage welder across the pond.
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dirtineye
Trad climber
the south
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Unrepentant vanity repost for my own words to be at the top, LOL.
Brian, I am not so sure about that.
It is possible that the shiny bit is the last thing that failed.
if it is on the compressed side of the bend , then this is almost certainly the case. If it is on the other side, then yes it probably failed first.
BUT, the odd color of the granulated stuff in the break really bothers me.
Incidentally, I agree that the bolt was installed at too great an angle, and not with the rign embedded, BUT, you probably should not drill straight up for a gluein, cause all that is holding in that bolt is the glue.
I think I have seen something in the past about NOT using glueins for this sort of application for that very reason.
Think about it. You have a smooth hole. You fill it with glue and stick a shaft in it. The Glue and the glue alone is going to deal with every downward force ever put on that bolt, and this is NOT the case in a normal gluein scenario, where the glue just holds the bolt still and the rock and the bolt do all the work.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Dirtineye - I did a bit of study of Hilti C-100 and HY-150 adhesives, and while I'm certainly
no expert, I can assure you that the compound literally becomes one with the rock;
there's absolutely no way the glue bond is going to fail before the bolt (virtually any bolt)
breaks. A while ago I posted a scanned experiment of the German DAV doing pull tests
of bolts that were specially designed to exceed the strength of the various glues in use.
The Hilti C-100 won out of all the glues tested, and failed at over 50 kN, far exceeding any
force humanly possible in a climbing application.
Hilti C-100 is what Ushba recommended for the Tortugas, and it's been replaced with HY-150.
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Russ Walling
Social climber
Out on the sand.... man.....
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This one seems bomber.......
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JLP
Social climber
The internet
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I'm focused on that ring. I doubt it's machined in, but possible. Machining is slow and expensive in Ti.
If it's pressed or rolled in, then the break happened right where the metal would yield the most during the process.
Any comment here on how that feature is put in?
The other bolts on the market use less agressive and intrusive features for the glue.
If the bottom of the ring were 8mm diameter, the bolt would be less strong than an equivalent 8mm rod, even less so if the metal was just yielded.
sigma = My/I for an 8mm rod is ~1E10 pa, with Ti alloys snapping at around 9E9 - assuming a 1kN load 5 cm from the break, normal to it. The 1E10 Pa # will actually be much less given the geometrey of the ring (it's a "stress riser"), and any possible yielding during manufacture.
Basically, the bolt design seems weak to me.
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Jay Wood
Trad climber
Fairfax, CA
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In the photo of the broken bolt end, you can see that the weld is opposite the shiny part of the break. So the bolt would have fractured until there was a thin section of metal left, which would bend before failing- like the 'hinge' when falling a tree.
From the in- place photo, it doesn't appear that the rock is cratered. It looks like it just wasn't inserted all the way.
P.S. I love my titanium (carpentry) hammer, and tried to love the Ushba nut tool, but the wire gate clip fell apart.
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dirtineye
Trad climber
the south
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Jay, that clip was a DUMB idea. and I told em so.
I had three of the old ones, they ROCKED. WEll they still rock, but I ground away the tip of one digging dirt out of cracks, and traded one to RRK, who since he never cleans anything, has a mostly perfect pre-clip Ushba nut tool.
I need to steal it back.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Well it certainly looks like my $100.00 is safe (to be honest, I was worried there for a sec).
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Brian in SLC
Social climber
Salt Lake City, UT
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Basically, the bolt design seems weak to me.
I don't think so. The bolt really should never have been loaded in the area of the groove/notch. That notch should be buried subsurface.
I swung the pictures by a metalurgist. Their comments were pretty consistant with a recent bolt failure we had here. Overload failure. Not initally maybe an installation issue, but, either the bolt wasn't installed deep enough, or, the rock cracked out under it. That created a pretty big moment arm in the bolt. Combine that with a now exposed notch, and you have a big stress riser. The shiny metal in the cross section picture indicates that there was a crack, for probably some time, maybe even years. Over time, it got a little bigger.
Although its hard to see in the picture, there appear to be parallel stop arrest ridges or striations along the direction of the crack. Also, there doesn't appear to be fatigue indications based on the surface (no cupping smiley faces facing towards the shiny crack).
So, I don't think its a bolt design problem. The bolt was darn strong enough for many years of dogging on it. Sooner or later, the small crack was going to reach critical flaw size and an overload failure was going to happen.
You could maybe poke at how the grooves/notches got in the bolt, but, they look pretty smooth to me. It'd be easy to imagine the bolt bending and developing a crack through repeated loading right there at the stress riser notch.
Would be interesting to get some high res. shots of the cross section surface.
Bottom line? Don't repeatedly fall on a bolt who's shaft is sticking part way out of the rock...
Coulda tied it off with a sling...ha ha. (Seriously, probably wouldn't have busted for years if it was tied off above the eye).
-Brian in SLC
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dirtineye
Trad climber
the south
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Hey ya know, there is no glues residue on the bit of bolt.
I thought HK said the new glues were super strong. Shouldn't some be stuck to that thing?
IF it were all gooped up with glue during the installation that is.
Maybe all the glue cracked off?
Here's a little secret about glue:
NO MATTER WHAT THEY SAY, ALL GLUE BREAKS DOWN EVENTUALLY.
If you help it along, it breaks down faster.
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Chiloe
Trad climber
Lee, NH
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The glue does not bond to the bolts. It bonds to the rock, and holds the bolt mechanically
(the reason for those glue grooves).
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graniteclimber
Trad climber
Nowhere
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Here is a post from the other forum:
"We used these directions installing the bolt Ushba
The shaft was sunk all the way into the hole.
I think the bolt was installed correctly.... but last Friday when we were attempting to install another, we noted that about a half inch of material could be removed from the surface of the ceiling with little effort.
What that means ( to me) is that it is possible that the bolt was sunk all the way to the shaft in Dec 2004, and over time, material near the hole fell of , exposing a half inch or more of the shaft.
This exposed shaft, then would be the brunt of stress. This could explain the bend seen in the photo.
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dirtineye
Trad climber
the south
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NO bonding to the bolt at all?
I guess that's why they want you to embed the eye a little.
ya know, I've seen epoxy used that did bond to the metal, on some glue-ins in NC.
Seems to me that if the glue does not bond to metal at all, then the rings should be something other than concentric rings.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Dirt - That's correct. These adhesives are mainly used to secure rebar, threaded rod, ect
into concrete. It's the threads on the rebar or rod that keeps it secure. It does knott
stick well to metal (if at all). Later versions of the Tortuga (and most likely the bolt in
question if it was purchased in 2004) have notches in them to resist lateral movement.
FWIW, a couple of the Fixe stainless steel bolts that were installed at Mickey's Beach
also rotate a slight bit; those bolts have dimples in them to resist lateral movement.
More info (my post from 2005) here:
http://www.supertopo.com/climbing/thread.html?topic_id=117902&msg=118438#msg118438
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jfs
Trad climber
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OK, I never post here but something's bugging me about that picture of the bolt in situ on the roof.
In the original pic of the broken bolt, the bend is AWAY from the eye. But, if I am seeing the second (roof) pic correctly(and I may not be)...it looks like the eye is hanging "below" the shaft of the bolt. I can definitely see that the shaft is sticking out from the rock too far...but shouldn't the shaft be bent in the opposite direction based on how it appears to be installed?
To put it another way, the broken bolt is shaped like a lower case letter "q" but it seems like it should have bent into a lower case "g" based on the in situ picture.
Am I missing something?
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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I've been thinking exactly the same thing. Let me repeat what I wrote in the 2nd post of this thread:
WTF?
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jfs
Trad climber
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That is unless...just to throw this out there and complicate things further...we are all seeing it wrong and it IS installed vertically (with the eye hanging on the right) and there's just some weird shading that makes it look like it's in at an angle. If you look closely it seems like this could be possible...???
Even if this is the case, the shaft is still exposed too much.
Potentially...years of rope dogging and lobbing off the hold outside the roof and swinging back and forth below...could have caused the stress needed? Especially if the choss broke off ONE side of the bolt only...exposing it to stress/bending in one direction only??? Or even if it was just 5 degrees off vertical???
Like HK said - a photo of the rock...
don't mind me...just trying to complicate things more. =)
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Chiloe
Trad climber
Lee, NH
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Here's a different photo posted on RC.com shortly after the bolt was first placed.
The way I read both this and the earlier photo, the eye is to the R, and the bolt itself
angled slightly up L (which would be consistent with the bend noted earlier).
Also, it sure looks like the shaft was already exposed.
Full context:
http://www.rockclimbing.com/photos/Sport/Hardware_was_approved.._47849.html
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graniteclimber
Trad climber
Nowhere
|
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The photo was added to rockclimbing.com on February 13, 2005 and the caption states the bolt was installed December 18, 2004, so it was already sticking out back then.
Larger version of the photo.
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JLP
Social climber
The internet
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" I don't think so. The bolt really should never have been loaded in the area of the groove/notch. That notch should be buried subsurface. "
The bolt is extremely weak compared to others on the market.
The glue will not prevent torsional nor tensile loading back to the ring feature.
The placement hole is larger than the bolt. Glue is soft. Therefore the bolt will bend somewhat in all cases.
Placement of the ring during the manf process may be yielding the metal, making it even weaker.
Loading the bolt in a laboratory and posting those #'s means very little.
I say the bolt is weak. I've decided I don't like it. If it were my design, I would change the ring feature.
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bwancy1
Trad climber
|
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This thread is awesome!
We have all read the posts regarding the disproportionally high number of climbers that are engineers, but who knew so many climbers are forensic metallurgists!?
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Chiloe
Trad climber
Lee, NH
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JLP:
The bolt is extremely weak compared to others on the market.
I claim no metallurgical expertise but ... how do you know this? Extremely weak compared to
what others on the market, in the warm marine environments for which the Tortuga bolt was designed?
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Brian in SLC
Social climber
Salt Lake City, UT
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Yeah, I don't know how you'd make a statement like that without knowing what the spec's on the Ti bolts were.
Speaking of which, the USHBA info on the net indicates its a special alloy? Anyone know what? Spec's?
Its a 10mm bolt with a fair amount of tensile strength, methinks. 120k or above?
-Brian in SLC
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JLP
Social climber
The internet
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Chiloe,
4mm vs 5mm radius x-section: over 2x the stress, therefore half the strength. That's for a straight bar. Tortuga has a stress riser with the ring that the other bolts out there don't. Corrosion of Ti is great, but that ring obviously needs to change. Strong design is not the same as strong material.
I am not a metalurgist, I am a development engineer. I make things work and I've been doing it for a long time.
How often have I seen this - 1 million reasons why the design can't fail - yet there is a failure. It's the stupidest mindset you can possibly have as an engineer. Remember all the BS about how styrofoam could never puncture the space shuttle wing? Look at CCH - that guy will be a pole dancer for the cowboys in Laramie in 2 years. Tons of data on his website about how great Aliens are and how they will never fail, but not one of them addressing why so many are failing.
BSLC - specs? You are picking through sand on the beach wondering why the hurricane hit. All alloys are in the same relative spectrum - and who even cares unless you have the exact load that broke it? There are several pictures of the broken item posted above with a pretty clear indication of why and how it broke - bending, torsion and tensile loading all at once - do you know Mohr's Circle?
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stevep
Boulder climber
Salt Lake, UT
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It broke further down the shaft because of a bad placement. Maybe a stainless gluein survives there, but maybe not. A bad placement is a bad placement. At least some of the stainless glueins I've seen have similar rings (which probably aren't machined in those either). Absent direct evidence that a stainless bolt in similar circumstances survives longer, I don't know that I'd call the manufacture faulty.
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tradmanclimbs
Ice climber
Pomfert VT
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From a photographers point of view the shiny spot may be a reflection/hot spot in the exposuer of the photograph and not an accurate depiction of the actual physical object.
From an old farts point of view who has broken lots of metal things, the shiny part is allmost allways the last bit to break.
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stevep
Boulder climber
Salt Lake, UT
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And here's the technical spec for the Petzl Collinox, one of the standard stainless glueins. Note the diagram showing that you should not install these with the shaft exposed. Note also the statement under Strength:
"The anchor breaking strength values indicated in the table depend
upon the quality of the supporting medium and the quality of the
placement.
PETZL cannot be held responsible for poor anchor placements."
I'd say the same goes for Ushba, or any other type of bolt.
http://en.petzl.com/ProduitsServices/P55%20COLLINOX%20P55500-E.pdf
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Evan Jackson
climber
Austin, texas
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Wowser, there's a whole lot of speculation without a whole lot of knowledge.
Please, if you are not familiar with the route keep quiet. Nothing compares to having firsthand experience with the route and the way the bolt was placed. Speculation about the environment/conditions only leads to more nonsense.
To clear a few things up, the hole was drilled perpendicular to the ceiling not at a 45. The bolt was fully seated with the eye pressed firmly against the rock the same way it’s displayed in the manufacturers instructions. Despite a clean shaft on the broken bolt glue oozed out of the hole during placement. Thus, the bolt was properly seated. Glue is still visible in the hole were the bolt used to be; it extends all the way to the exposed rock surface. Please, take a look at the lefthand side of the eye and you will see that the straight part of the eye does extend into the rock at a true vertical orientation. The dark shadow that people mistakenly believe is the shaft extending at a 45 is actually extra glue that oozed out during installation.
I will be there this weekend and gladly take pictures. I’ll try sticking a pencil in the hole so all can see its access runs normal to the roof plane.
The bolt was placed by individuals with years of experience and literally hundreds of bolts to their name. It was placed correctly according to the manufacture’s instructions and common sense.
Please, if you are not an engineer be quiet, layman speculation is what leads to rumors and false climbing myths.
The bolt broke at the “threads” this could have easily acted as a stress concentrator.
The fracture surface does exhibit signs of fatigue (a common failure mode in both steel and titanium). The small shiny area could be an area of slow crack formation. The uniformly tiny dimpled area is characteristic of fast fracture. Which occurs only after slow growth has reached a critical point.
The bolt was placed in such a manner that falls were small and never came close to a class two. It was mostly loaded with body weight only. Another crack is also present near the weld. Something else is going on here. Two cracks in one bolt that only handles low force is peculiar. Even the weld quality differs between this bolt and the picture that Chiloe posted.
Corrosion is not an issue; the bolt was placed in a limestone roof. It was never exposed to chemicals and barely even saw moisture.
As SteveP stated even 6sigma standards can yield a product that fails. Perhaps this truly was the lottery winner.
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Dr. Rock
Ice climber
Castle Rock
|
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Thank you for that.
I will try and not speculate, but I do have a little more background info.
Yes, I kind of went of half cocked there, hell, I don't even have the parts.
I better go yank the Pirate pic.
Sorry Lord Slime!
This hanging load can be classified as a Satic or "Dead" Load.
There are two types of Static loads.
Compression and Tension.
So this would be classified as a Dead Tension Load.
The load that the part will handle is determined by it's Tensile Strength.
You can easily look up the Tensile Strength of various metals on the web.
Lets use a worst case scenario, Al alloy.
Tensile Strength of about 40,000 lbs per sq inch.
(Love those English Units, no jokes please)
OK,lets really jack up the odds and say the Net Bolt Diameter, as opposed to the Total Diameter (the scoring reduces the Net Diameter)is a 1/4 inch.
OK, Pie R Squared is the area of a circle.
So, a 1/4 inch bolt has a 1/8 inch radius.
Area is therefore 0.05 Sq. Inches.
Heck, lets drop the Tensile Strength down to Shear Strength, which is about 30,000 lbs per sq inch.
So 30,000 Times 0.05 = 1500 Lbs.
That is for a 1/4 inch Al bolt, using Shear, not Tensile.
Since the equation for the Area of a Circle is Quadratic in r, the Tensile Strength rises rapidly as the diameter is increased.
Other things to consider:
Glue expansion rate vs Ti alloy expansion rate.
If the bolt could turn, then it could be bent back and forth.
In order to deform a steel rod, you have to apply a force greater than it's rating.
When this happens, the metal stretches as the force is increased, until a point is reached where it will not bend anymore, the force goes down a tad, then Snappy Gator.
So we do not know if the bolt was deformed before or after the fall.
One thing, welding a complete 360 weld on a part that small will really heat it up.
If it were held in a metal jig, there could be a heat soak right at that point, causing a differential in metalic properties.
Also, if you use this as a ceiling hanger, the eye should be oriented so that a load will be placed in line with the vertical axis.
If you look at the Petzl link, full props stevep, you will see this is what they have done.
We could look at the Modulus of Elasticity for Ti alloy, that might be cool.
The reason they do not make Ti Biners is because the alloy does not like to be bent that much.
I think the only way to build this Ti bolt would be to increase the Net Dia., add bumps instead of grooves to hold the glue, put the eye on the C/L, machine the part or find a welder from the Nasa program.
One last thing, when you weld a closed loop like that, there is no expansion joint.
I went through this back in 84 when they had a recall on Ritchey Bull Moose Alloy handlebars.
They were way cool, I wish I could find a set.
The stem, and bar were one, complete with brake hanger.
But there was an equi lateral triangle of welded, heat treated alloy.
And they cracked like a Mo.
OK, I'm Out.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Dr. Schlock - please give it a rest already...
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Russ Walling
Social climber
Out on the sand.... man.....
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zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
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Dr. Rock
Ice climber
Castle Rock
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Eureka!
When ceiling installed, the eye orientation will produce shaft deformation, due to a misalignment of forces, eventually leading to catastrophic failure over time due to cyclic static loading.
So although these bolts may be perfectly fine for vertical wall placement, witnessed by the many already in place, I would think twice about hanging of a Ti ceiling bolt.
The good news is that there are probably relatively few ceiling bolts of Ti compared to wall bolts?
That, I do not know.
And how do you tel steel from Ti?
Carry a magnet?
That is my final answer.
Next thread?
Next victim?
Judd, For The Defense.
Hah! Remember that one!
Then you might remember O.K. Crackaby?
And man, did Burl Ives have a crack!
But I don't think he ever smoked crack.
Charlie Daniels, maybe.
Hoyt Axton, definately, but not Burl.
Man, how would you like to be on the crux at Washington Column, and you look down and see Burl Ives on Crack, crawing up your rope with a dagger in his mouth and a gitar on his back, Ho Man!
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Dr. Rock = Drkodos.
Dirtineye nailed it.
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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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JLP
Social climber
The internet
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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.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
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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.
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Evan Jackson
climber
Austin, texas
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“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)?
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pud
climber
Sportbikeville
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
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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.
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Chiloe
Trad climber
Lee, NH
|
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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.
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Chiloe
Trad climber
Lee, NH
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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.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
|
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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.
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Ain't no flatlander
climber
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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.
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graniteclimber
Trad climber
Nowhere
|
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Ain't no flatlander: "The guy who decked has only himself to blame."
Can you explain how you know this? Ushba recommended the device for top-rope soloing and he was top-rope soloing. (I edited the post to say this.) You do not know that the device was shock-loaded. Also, you don't know that he grasped the device during a fall.
The guy who decked should have used back-up knots, but if the ascender failed it shouldn't have.
You weren't there. You have no idea what happened. But just that doesn't stop you from saying you know who is too blame, just like the posters blaming the failure of the Tortuga bolt on the installation.
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sawin
climber
So. Cal.
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navblk4 like yourself does not appear to be prejudicial here.
He stated think.
I think the other request of yours with the reward is beneficial
for determining further facts.
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dirtineye
Trad climber
the south
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Hmmm, I sent a link to this thread to Liberty Mountain yesterday, and asked them to come explain what they could about those tortugas.
Still waiting.....
Now. before, when Ushba was in charge of this stuff, I used to talk to those guys all the time on the phone. They sent me a special Piton one time (which got stolen off the route GODAMNITALL) to put non corroding pro in a wet section of a climb, and I got one of the old version of the ti nut tool, plus they told me a lot of information about titanium climbing gear applications.
Wish I could get in touch with those guys about this. I know they'd take it seriously.
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Dr. Rock
Ice climber
Castle Rock
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OK, I am doing the math on this, film at 11, but one interesting thing has come up.
With this design, it is actually better if you do mis install it and leaver a little shaft hanging out.
So that eliminates the install as a variable.
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Dr. Rock
Ice climber
Castle Rock
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Degrees from eye bolt axis vs. Percentage of stamped load-lifting capacity available:
15 degrees 55%
30 degrees 35%
45 degrees 25%
90 degrees 20%
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graniteclimber
Trad climber
Nowhere
|
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Can someone provide those pictures that Hardman is asking for?
When photographing the hole, please (if possible) use a digital SLR camera set to low ISO. (The last set of pictures were taken with an Olympus 350 point and shoot at ISO 200 and are grainer then they need to be.)
Are there any good pictures of the bolt before it broke? If there are not, push the broken-off piece back all the way into the hole and photograph that from different angles.
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dirtineye
Trad climber
the south
|
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Will someone tell DRShlock to STFU?
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Brian in SLC
Social climber
Salt Lake City, UT
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Hmmm, I sent a link to this thread to Liberty Mountain yesterday, and asked them to come explain what they could about those tortugas.
They're swamped right now with the OR in town. I saw them quaffing beer, uhh, I mean working last night...
They've really not got much USHBA stuff in stock, and, no plans to re-order from what I've heard.
They're the distributor. Not sure what they'd bring to the party with regard to the busted bolt issue. Worth a try, I guess.
Surfing around the 'net, I see the Thai folks have done a ton of bolt replacement using Ti, but, a bolt "like" the tortuga. Anyone know anything specific about what bolts they are using? Seems like they got a direct source for a custom job or some such? Sam probably knows...
Cheers,
-Brian in SLC
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jstan
climber
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Perhaps, after all is said and done, the leader really should not fall?
Are we coming all the way round? I have seen curiouser.
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Ain't no flatlander
climber
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Granite spewed once again "Can you explain how you know this? Also, you don't know that he grasped the device during a fall. "
According to NorCal, that's exactly what he did. Plus he failed to use a backup, which is a fundamental error. The device cannot be blamed yet you and NorCal want to discredit all products the company made based on this.
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graniteclimber
Trad climber
Nowhere
|
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I wrote: " Also, you don't know that he grasped the device during a fall."
Ain't No Flatlander responded: "According to NorCal, that's exactly what he did."
Edited because I was wrong: Nor Cal said " he grabbed the rope during his fall and this prevented his ushba from camming into place."
Ain't No Flatlander is right that the accident was user error.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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As I remember it, Nor Cal said the guy grabbed the rope, which prevented the device from locking up...
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Dr. Rock
Ice climber
Castle Rock
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If you go down to OSH and look in the Fastner section, you will see that even the 79 cent galvanized eyebolts from China are built with the eye along the centerline.
In fact, I do not recall ever seeing a design of this type.
This is not rocket science folks, you have Gravity, you have a Load, which creates Stress.
You have a piece of hardware that has a load rating.
When the Load is Exceeded, the Apple falls to the Ground and breaks his feet.
I mean I can see Mongo the Caveman, out climbing.
Mongo fall on wood bolt.
Mongo hurt knee.
Mongo build bigger bolt.
Doh, ...
We are going to Mars pretty soon.
Can we build a good piece of hardware from 1920, or is that too much to ask?
As soon as you put the eye off center, you are loading the shaft with a vertical component as well as a horizontal.
It does not like the vertical, or "sheering" load.
wrong.
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Hardman Knott
Gym climber
Muir Woods National Monument, Mill Valley, Ca
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Dr. Schlock wrote:
Mongo fall on wood bolt.
Mongo hurt knee.
Mongo build bigger bolt.
Dr. Schlock finds this thread.
Dr. Schlock doesn't know shít.
Dr. Schlock keeps on posting...
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jstan
climber
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I read enough of the thread to reach the one reporting the weld did not look like Chiloe's stacked coins but was like a blob, and it cracked.
A suggestion. This bolt should have been rejected at manufacture. Welds need to be closely controlled especially in a material with less experience in the field than possessed by steel.
If a part with a problematic weld was released from production one might expect there may have been other problems during manufacture of this unit. If corners are being cut, it is unusual to find only one corner has been so handled. If you still have the bolt, materials analysis would appear to be in order. Hardness, impurities, grain size, yield modulus etc, etc,etc. And if at all possible, have the analysis done by a vendor who makes personal safety equipment in titanium. Only they will be adequately familiar with the ins and outs of working this material. It may be the needed technical experience exists in Thailand if that is where this material is being used extensively.
Send both parts for analysis!
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Dr. Rock
Ice climber
Castle Rock
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The bolt should have never been released for production in the first place.
It is a faulty design.
The good weld was from a part that was shown at the USHBA website.
But again, the weld is not the problem.
A simple tack weld, however, where the loop rejoins the shaft, would have been better.
It would be plenty strong to hold the loop closed, but would not heat up the part as much.
You have to flip that part when you weld it 360.
With Ti, you have to keep the Argon gas flowing over the weld during the flip over.
If you don't, you lose coverage and the weld cracks.
USHBA is aware of the problem.
Mr Slime is aware of the problem.
Now, thanks to the internet and the wonderful forum, the climbers are aware of the problem.
At this point,it's all about Damage Control, thus, the visits from the Manufacturing Sector.
When you design products for Human Safety, you better know what the H you are doing.
And test the Hell out of it.
Hopefully, the people climbing in Thailand do not weigh as much, and I hope they are over the ocean.
Easier to get away with stuff in a foreign country, eh?
What are they gonna due, fly over and file a lawsuit?
Not with these gas prices.
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stevep
Boulder climber
Salt Lake, UT
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Seems like a lot of assumptions about their weld process. Ti is certainly not easy stuff to work with, but that isn't to say it can't be done right, and I'm not clear that the problem in this case was manufacture.
If the bolt had simply broken, I'd be much more inclined to say bad bolt. But I can't really think of any way that bend gets there other than the bolt shaft was exposed more than it should be. And again, Petzl says that is bad for their steel bolts as well.
Be curious to see what the feedback is from Thailand on this. I believe there are quite a few of these in a horizontal roof at Tonsai. Seems probably a better sample to draw conclusions from than this single incident.
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Dr. Rock
Ice climber
Castle Rock
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Steve, remember when I said that it would be better if the bolt wer Not installed all the way?
Look back at that Free Body Diagram.
The more shaft exposed, the more metal to bend and take the strees.
But when an offset eye is set in to the the limit, you have all that leverage in the X direction, which is what broke the bolt.
Remember, theses guys were testing the thing by jumping off of it.
This no doubt, because of the design, started the bending process, which continued until the the ultimate load was reached.
I do not like seeing bones sticking out of peoples legs, thus the interest in this thread.
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dirtineye
Trad climber
the south
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DrRock, YOU ARE AN IDIOT.
You are WRONG about the shaft sticking out being good.
Torque = the product of a force and the length of the lever arm, and you'd know that if you had any background at all for this stuff.
Making the shaft longer is WORSE. Embedding the eye up to it's neck is what you want.
GO here and see if you can comprehend.
http://en.wikipedia.org/wiki/Torque
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Dr. Rock
Ice climber
Castle Rock
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I am Not an Idiot.
I am a Moron, remember?
An Idiot has more Brains than a Moron.
Look it up.
Don't give me more credit than I deserve.
But the Internet is full of people better looking and smarter than me, I can use them to help me, right?
That is the purpose of the Net, at least originally.
No seriously, imagine clamping a nail in a vice and bending it back and forth til it breaks.
Which is going to be easier as far as breaking it off is concerned, grabbing it at the nearest point to where it is clamped, or grabbing it at it's end?
If you grab it at the end, the bending can be distributed along the portion of the nail that is exposed.
If that portion is very short, like when you grab it at the vice, then you have very little steel to help share the load, get it?
It is going to see a Sheering Forced, not a Tension Force.
We want the Tension Force, but the Sheering Force we do not like.
We try to design that variable out of the product.
Go back and stare at that diagram for how ever long it takes.
A picture is worth a thousand words, the failure mode is cleary visible.
Now go down to the Hardware Store and look at eye bolts.
See how the eye is lined up with the shaft as to not put any sideways pressure on it?
You got the most fit people in the world, maybe even the smartest, they are out enjoying nature, and the wonderful body and landscape that God sent them, they are doing the most natural and organic thing you could possibly due in life, climbing. Everything is wonderful in this fantasy like world, then something brings you down to Earth, literally. What is it?
A component designed by some guy that spent his life climbing, noticed that it did not pay very well, although it was a lot of fun, as well as a lifestyle, but I am getting old, what to do?
Start a company that sells rock climbing equipment, get some friends together, get some QBE engineers, go have a drink or two, start the company, put out a bad product, and retire to the poor house early becuase of all the laws suits you forgot about.
Im just hope this guy did not get any of your money.
Bummer in the summer.
Beter luck at you next venture, I hope it pays.
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dirtineye
Trad climber
the south
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Dumbass, you still miss the point.
You are clueless, and have NO understanding of what is going on there. Copy all the crap off the net you want, you still won't understand it any better than a trained monkey would.
If the eye is embedded and glued the way it is supposed to be, BOTH ARMS of the eye will take stress, as opposed to your idiotic notion that it is good for the single shaft to be under stress.
One more time, the further that shaft sticks out, the more torque you can put on it. That's bad.
STFU.
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Dr. Rock
Ice climber
Castle Rock
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Ahh, I see what you are saying.
With the shaft hanging out, there is more leverage on the part.
Yes, that is true.
Hmmm, let me thing about this for a bit.
Meanwhile, try and visualize a Karate guy breaking a board.
What if the board were held by supports that were ten miles apart, would the board bend when he hit it, or would he snap like through it?
What would happen if the board were supported by a couple of cinder blocks that were only 6 inches apart.
So you have a point, I have a point, interesting problem, shaft flex vs leverage, which is worse?
Dirt, imagine the same bolt in a ceiling, only hanging down from it's now longer shaft by ten feet.
What would happen when you hung a load of of that thing?
Would the shaft flex gradually over that ten feet, evenly distributing the horizontal vector, or would it do the Snappy Gator?
I do not mind a little conflict BTW.
I have been in forums were everybody agrees with one another, and everybody is nice, but nothing gets resolved!
And it is boring as hell.
So yeah, if you are new to the forum bidness, it can be a rough ride folks, try not to make too many enemies, you never know who is out there, this one forum, ol Fletcher over at Gear Slutz was gonna call the Hells Angels out because a guy insulted his wife, it can get pretty ugly and maybe dangerous, so it is a good idea not to use pics or your real name, just in case, if you have ever met someone from the internet, you know what I mean.
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dirtineye
Trad climber
the south
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You
Still
Don't
Get
It.
IDIOT!
Did you not see the earlier posts about bending a rod of any sort enough times? Metal fatigue always wins, because metals are not self repairing, like organisms. Now, if you had a bolt that could heal itself, then you might have something, but you don't. Nobody does. They don't exist. Am I making this clear enough for you?
Hey DrDumba$$, imagine how nice things would be if Pi were three. Hell, the bible says it is. Imagine how much easier things would be then.
And what if 2 + 2 could just equal whatever you wanted, instead of coming out that pesky old 4 every time.
As for meeting you, I'd love to. It would be a rare experience.
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jstan
climber
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Imagine a right circular cylinder, a bolt, bent over a circular mandrel. Now the end of the cylinder that is bearing the weight is not going to suddenly look as though it had been cut on an increasing angle as the bolt is bent further around the mandrel. Think about it and you will see materials don’t distort that way. The end stays square. Now let’s say the mandrel is six inches in diameter and the bolt is 0.5 inches thick. The side of the bolt contacting the mandrel will wrap around the mandrel in an increasing angle of bend. If we express the angle in radians we can measue out the length of that side of the bolt that is in contact with the mandrel. Our old friend
S=rø
So if we wrap through an angle ø on a six inch diameter( radius 3 inches) the length of the bolt contacting the mandrel will be
S1=3*ø
But the far side of the bolt will be bent over a radius one half inch larger so the outer surface will have a length
S2=(3+0.5)*ø
OK so the outer surface of the bolt is being stretched relative to the inner surface. This is a dilatation and what is the fractional dilatation? It will be
(S2-S1)/S1=(3.5ø-3ø)/3ø=0.17
Cool, but let’s bend the bolt around a 0.1 inch mandrel. Then the fractional dilatation of the outer surface of the bolt will be
(S2-S1)/S1=(.51ø-.1ø)/.1ø=4.1
Twenty five times larger and we now have to worry about that outer surface exceeding its yield modulus and the bolt failing.
Now here is something more interesting. If you let the bolt stick out six inches the eye will move a whole lot but the radius over which it is bent out in the extended shaft will be something like half the distance it sticks out. The fractional dilatation won’t be all that much even though it moves a lot. Materials fail when their modulus is exceeded not when a long length of it bends a long distance.
In order to apply this to the bolt in question we need to know the actual geometry. If you have that and you look up materials data on titanium having the temper possessed by that bolt, you can do a calculation.
My guess? We don’t know the properties of the material in that bolt at the point where it failed.
A friend of ours fell while climbing and shattered her heel bone beyond reconstruction. In her case she subsequently ran into auto-immune problems. You really don’t want to damage your feet this way.
My advice? When you are with a big group of people whooping, hollering, and acting like they have nothing to fear down there, take care to realize they are correct. You are the one who has something to fear. I had a second once who took it into his head to yell at me and urge me to go for it when I was busy figuring out the move. You run into people like this who know zip and think cheering someone on to risking their neck is cool. Avoid them. When things get serious you don’t want them around, anywhere around. The further away the better. The next state is not far enough away. Next galaxy…..that’s OK. Two or three galaxies away ….now that’s getting better.
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Dr. Rock
Ice climber
Castle Rock
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Cool on the Polar system, been a while.
One rev is 2 pi radians, right?
Idaho National Engineering and Environmental Laboratory
* Improper use of rigging gear can result in equipment damage, personnel injuries, and even death
* So-called “experts” sometimes aren’t
* Guidance and standards can be misleading
* When in doubt, stop work and start asking questions
(and a little bit about proper use of shouldered eyebolts, too)
Oh, wow:
"It should be noted that bolts do not come under the category of Personal Safaty Equipment and therefore do not require independant testing and carry no CE mark."
Open season.
Ushba Bolt (Buhler type glue-in developed for Thailand to overcome the corrosion problems)
Material. Titanium:10mm dia. 5 tests. 9kN, 9kN, 10kN (all broke at eye weld), 24kN, 34kN.
From Bolt Products.com:
"Welded Eye Bolt
Usually threaded on the shank to provide a good bond this is a traditional design which comes in and out of popularity. While a number of these have proved to be reliable there are two areas of concern. The first and main one is the welding, without correct material selection and a very experienced welder this will always be a weak point, with too rapid cooling of the weld area leading to cracking and failure of the shaft itself. The DAV have tested a large number of these (a home-made series) and had shaft failures as low as 50N! "
FMI:
Here is a table of the range of strengths for typical rock types.
Unconfined compressive strength:-
Granite 100-250 N/mm²
Basalt 100-300 N/mm²
Quartzite 150-300 N/mm²
Sandstone 20-170 N/mm²
Shale 5-100 N/mm²
Limestone 30-250 N/mm²
Marble 100-250N/mm²
Slate 100-200 N/mm²
Quartzite 150-300 N/mm²
Concrete 14-42 N/mm²
High strength concrete 70 N/mm²
"Myth 4:- Titanium is light, strong and corrosion resistant. Pure titanium is in fact quite weak and soft, ASTM grade 1 having a tensile strength of only 240N/mm². (`mild´ ASTM 1018 steel is 440N/mm² ). Alloyed with aluminium and vanadium (grade5 for instance) gives the highest tensile strength of 896N/mm², about the same as cold worked stainless steel and chrome-molybdenum. Unfortunately in this condition it is prone to stress corrosion cracking in the presence of salt so for sea cliffs one needs to add palladium, ruthenium or possibly nickel. A good choice for pitons would be something like grade 27, a `low´cost titanium/aluminium/vanadium/ruthenium alloy.
`Low cost´ is relative as ingot prices start in in the hundreds of thousands of dollars per ton and I would expect to be paying over €300,000 per ton for rolled material!
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perswig
climber
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What's the possibility this bolt suffered some 'creep' from it's glue bed over time?
Vertical placement, repeat body-weight loads plus random falls. Installer says placed at correct depth; no rock fracturing, etc reported during post-break inspection; some of pre-break pics show shaft visible; fracture appears at/close to first groove in shaft; some question of position of 'eye' in pre-break pics vs. direction of fracture.
If the glue binds to rock but not to the bolt; if the bolt were placed in a way (too little rotation during installation, after glue had started to solidify, whatever - I can see this being difficult to do timing-wise in this position) that doesn't allow the glue to fill the relief grooves, just creates a cylindrical bed.
Can this allow rotation of the bolt in place? Can the bolt migrate until enough of the shaft is revealed to allow repeated stress to fracture at an obvious and unintended weakness (the groove), regardless of all the metallurgy, weld specs, etc.
Just asking.
Dale
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jstan
climber
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Well, Doc, I think you may be getting somewhere. Heat processes and alloy segregation become a huge liability anytime you are working an alloy like this. Besides the weld this material has to be heated to form the eye. They may get the heating and cooling right to make the eye strong but what about the shaft? Presumably such a product would have to go through a carefully controlled annealing to rectify such problems. Then if it is a personal protective product you need to test a big portion of the product stream to destruction to get the needed statistical confidence.
I expect GE spent billions to develop the materials technology that made the jet engine possible.
We like to think technology has allowed us to distill climbing down to just the endorphine buzz. The risk component can be driven off. There is risk in gymnastics. Plenty of risk. Gymnastics, IMO, is to climbing like the jet engine is to this bolt. What we are doing in climbing is really very crude.
As Jay Wood notes there is risk in my using this computer. Risk is a part of life. That is what I liked about trad climbing. You actually got to choose how much risk you would undertake and then you could learn to function with safety acceptable to you in that environment. Climbing was not about difficulty ratings. Ratings never were anything more than a toy for people who did not realize what it is they were really doing.
We are learning to be aware of our surroundings and learning to live and function in those surroundings. Exciting stuff,
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stevep
Boulder climber
Salt Lake, UT
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The lever arm is worse for the bolt. Again I refer you back to the Petzl spec. They clearly recommend against leaving the shaft exposed in their symmetrical stainless bolts. So material and eye design might have an impact in failure, but unless you also think Petzl's engineers have it wrong, having the shaft exposed where it could be bent is a bad idea regardless of material.
If someone can come up with an alternate mechanism for the bending of the shaft in this accident, then maybe I'll start worrying about large numbers of these bolts being bad.
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JLP
Social climber
The internet
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"Twenty five times larger and we now have to worry about that outer surface exceeding its yield modulus and the bolt failing. "
If the metal stayed bent, it yielded.
"If you let the bolt stick out six inches the eye will move a whole lot but the radius over which it is bent out in the extended shaft will be something like half the distance it sticks out"
You have either forgotten Mohr's Circle, or never been exposed to it. This allow a radius thing isn't even academic.
More to the point, anyone with a 1/2 oz of experience will immediately recognise that any bending or torsion will greatly magnify stress at the ring feature - the feature that actually failed.
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dirtineye
Trad climber
the south
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Thank you JLP.
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Dr. Rock
Ice climber
Castle Rock
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Good stuff.
I think we have arrived at Elasticity.
This could have been a big box of Russian Surplus.
No, even the Rusians would laugh at this design.
Export to Gerogia, maybe.
No, even that would be too cruel.
What is worse than a Kinematical Death?
Trapped in a burning car is the only thing that beats free fall.
Drowning is relatively painless, you just slowly pass out.
There has never been a recorded Malfunction of the G Field.
Not for one nano second.
So do not count on a Malfunction when it comes to Gravity.
Thats why we have to be Perfect in everything we associate with climbing ten feet or more.
The Petzl is forged, BTW.
Modulus:
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Dr. Rock
Ice climber
Castle Rock
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OK, here is what the fine Gentleman was talking about when he mentioned mandrels and I/O radius drama.
Just adding a shoulder washer dramatically increases the strenght of the system.
Why?
It adds radius to the edge.
Just enough so the bolt does not sheer.
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fear
Ice climber
hartford, ct
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WHOA!
You mean to tell me that bolts that people have been hanging and falling on for months sometimes fail???!!!
HOLY SHIZNIT BATMAN!
Tell me it isn't so....
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jstan
climber
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JLP's points were all good. i just had to come up with an understandable explanation of why radius of curvature is important, and if that is a factor that is where you may get failure. I have seen enough pitons and such bent all out of shape without breaking to cause me to worry about things in addition to bending.
The picture I saw showed a bolt broken cleanly with relatively little bending. That and Doc's discussion of how this material is alloyed convinces me absolutely and never to count on such a bolt as my only protection. But that is me and you folks are you.
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