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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]
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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]
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[snip quoted text from Lord Slime]
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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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