Titanium Bolt Failure.

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Messages 163 - 182 of total 195 in this topic << First  |  < Previous  |  Show All  |  Next >  |  Last >>
dirtineye

Trad climber
the south
Aug 7, 2008 - 10:54pm PT
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.

Dr. Rock

Ice climber
Castle Rock
Aug 8, 2008 - 01:08am PT
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.
Dr. Rock

Ice climber
Castle Rock
Aug 8, 2008 - 01:54am PT

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%


graniteclimber

Trad climber
Nowhere
Aug 8, 2008 - 02:15am PT
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.
dirtineye

Trad climber
the south
Aug 8, 2008 - 07:46am PT
Will someone tell DRShlock to STFU?
Brian in SLC

Social climber
Salt Lake City, UT
Aug 8, 2008 - 10:16am PT
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
jstan

climber
Aug 8, 2008 - 10:24am PT
Perhaps, after all is said and done, the leader really should not fall?

Are we coming all the way round? I have seen curiouser.
Ain't no flatlander

climber
Aug 8, 2008 - 11:23am PT
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.
graniteclimber

Trad climber
Nowhere
Aug 8, 2008 - 11:42am PT
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.
Hardman Knott

Gym climber
Muir Woods National Monument, Mill Valley, Ca
Aug 8, 2008 - 12:20pm PT
As I remember it, Nor Cal said the guy grabbed the rope, which prevented the device from locking up...


Hardman Knott

Gym climber
Muir Woods National Monument, Mill Valley, Ca
Aug 8, 2008 - 12:34pm PT
I think this post from the German Alpine Club glue-in test thread is very relevant to this discussion:

http://www.supertopo.com/climbing/thread.html?topic_id=406815&msg=650426#msg650426
Dr. Rock

Ice climber
Castle Rock
Aug 8, 2008 - 01:11pm PT
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.
Hardman Knott

Gym climber
Muir Woods National Monument, Mill Valley, Ca
Aug 8, 2008 - 01:19pm PT
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...

jstan

climber
Aug 8, 2008 - 01:45pm PT
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!
Dr. Rock

Ice climber
Castle Rock
Aug 8, 2008 - 04:47pm PT
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.
stevep

Boulder climber
Salt Lake, UT
Aug 8, 2008 - 08:37pm PT
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.
Dr. Rock

Ice climber
Castle Rock
Aug 8, 2008 - 08:46pm PT
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.
dirtineye

Trad climber
the south
Aug 8, 2008 - 09:36pm PT
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

Dr. Rock

Ice climber
Castle Rock
Aug 8, 2008 - 10:39pm PT
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.


dirtineye

Trad climber
the south
Aug 8, 2008 - 11:18pm PT
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.

Messages 163 - 182 of total 195 in this topic << First  |  < Previous  |  Show All  |  Next >  |  Last >>
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