Sheared Clean Off

If it doesnt fit anywhere else but you still want to share, this is the place
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Cybrludite
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Re: Sheared Clean Off

Post by Cybrludite »

I'm going to go ahead & claim that aliens beamed the wheel off for nefarious purposes of their own. :mrgreen:
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Yogimus
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Re: Sheared Clean Off

Post by Yogimus »

Check the rim on the other side, see if it is "ovaled" out
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Darrell
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Re: Sheared Clean Off

Post by Darrell »

Does the hub still turn?
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Kommander
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Re: Sheared Clean Off

Post by Kommander »

I have actually seen somthing like this before. It was some time ago so I don't remember details but a summer camp I worked at had this happen to a full size truck. However some of the threaded bolt stumps were rusted where they had broken so it appeared that the bolts had not sheared all at once but over the span of some time.
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Yogimus
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Re: Sheared Clean Off

Post by Yogimus »

Theory: The hub has a "tight" spot along its rotation, not enough to cause vibration, but enough to start warping the rim. The warped rim then starts working on the bolts.
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Termite
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Re: Sheared Clean Off

Post by Termite »

It's just plain weird.

I'm starting to think that Murphy has made it personal with Chris......... :shock:
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Aesop
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Re: Sheared Clean Off

Post by Aesop »

Yet another argument for redundant redundancy in anything critical.

Mazel tov!
"There are four types of homicide: felonious, accidental, justifiable, and praiseworthy." -Ambrose Bierce, "The Devil's Dictionary"
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Termite
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Re: Sheared Clean Off

Post by Termite »

Aesop wrote:Yet another argument for redundant redundancy in anything critical.

Mazel tov!
What's the old SEAL saying? "One is none, and two is one?" Something like that.
"Life is a bitch. Shit happens. Adapt, improvise, and overcome. Acknowledge it, and move on."
Aesop
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Re: Sheared Clean Off

Post by Aesop »

Glad you're around to blog about it now.
"There are four types of homicide: felonious, accidental, justifiable, and praiseworthy." -Ambrose Bierce, "The Devil's Dictionary"
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blackeagle603
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Re: Sheared Clean Off

Post by blackeagle603 »

In addition (or duplicating) what's already been discussed here...

Doing failure analysis of metal interconnects is sort of a day to day thing at work (albiet in a different domain of forces and metal currently). I see shearing like that and my first action is uneditted brainstrom with first/all thoughts that come to mind then follow each of those threads with a ponder on what inspection/failure analysis tools are available to test each theory.

- uniformly overtorqued studs
- low grade/defective metal
- perhaps some uniform scoring/damage of the studs from the rim that created a stress riser and allowed cracks to propogate
-perhaps uniformly undertorqued nuts which allowed the rim to work on the stud and create stress riser for crack propogation. Normally loose nuts would get thrown first. Maybe thought, if nut/stud thread stiction was high enough it could hold a loose nut on the stud while the stud was worked to failure by the fretting rim.


Is there any fretting/witness marks on the drum/hub that look different from the surviving wheels?

Can the stud remains be extracted and hardness tested/x-sectioned and grain structure be examined on a metallurigal scope?

Had the studs been previously overtorqued by tire shop? Any way of knowing that/comparing to other rims and lugs that may been installed by them and not yet removed by you?
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