strut tower failure
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From: On a pygmy pony over by the dental floss bush
. Do the brackets tie to the strut tower or body of the car anyplace besides the three fasteners on the top of the tower?
Three Wheelin'
Joined: Oct 2003
Posts: 1,489
Likes: 17
A metalurgical post-script...
I was able to get the part examined (thoroughly but 'unofficially'*) by a metals lab, and there were some aspects of interest.
They were not told, but from their tests they were able to identify the metal as from Porsche, because it is apparently a proprietary aluminum alloy that is very strong. I would guess that any shop that ever simply tries to weld one of these back together would be fighting a metallurgical battle they couldn't win.
They found that my part had two fracture surfaces, meaning that a crack had occurred much prior to the date of my road incident, and the complete failure was induced by enough new jolting to break the rest of it. It seems we should define a regular inspection protocol for this part, and perhaps a concerted consideration of the club-sport reinforcement part, and a write-up on what it takes to install? I still have most of the broken part to examine. I would want to make sure the reinforcement actually added support where the fracture occurred...
*The information was delivered unofficially, delivered by word-of-mouth only, for free as a kind and generous professional courtesy. They can make this information available in a formal detailed official engineering report, for a time, if it is paid for, and it is not likely to be cheap. This is because an official report exposes the testing company to time spent later, in involvement in any business or legal proceeding in which the report might become material.
HTH,
Joe
They were not told, but from their tests they were able to identify the metal as from Porsche, because it is apparently a proprietary aluminum alloy that is very strong. I would guess that any shop that ever simply tries to weld one of these back together would be fighting a metallurgical battle they couldn't win.
They found that my part had two fracture surfaces, meaning that a crack had occurred much prior to the date of my road incident, and the complete failure was induced by enough new jolting to break the rest of it. It seems we should define a regular inspection protocol for this part, and perhaps a concerted consideration of the club-sport reinforcement part, and a write-up on what it takes to install? I still have most of the broken part to examine. I would want to make sure the reinforcement actually added support where the fracture occurred...
*The information was delivered unofficially, delivered by word-of-mouth only, for free as a kind and generous professional courtesy. They can make this information available in a formal detailed official engineering report, for a time, if it is paid for, and it is not likely to be cheap. This is because an official report exposes the testing company to time spent later, in involvement in any business or legal proceeding in which the report might become material.
HTH,
Joe
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From: ^ The Bay Bridge
I was able to get the part examined (thoroughly but 'unofficially'*) by a metals lab, and there were some aspects of interest.
They were not told, but from their tests they were able to identify the metal as from Porsche, because it is apparently a proprietary aluminum alloy that is very strong. I would guess that any shop that ever simply tries to weld one of these back together would be fighting a metallurgical battle they couldn't win.
They found that my part had two fracture surfaces, meaning that a crack had occurred much prior to the date of my road incident, and the complete failure was induced by enough new jolting to break the rest of it. It seems we should define a regular inspection protocol for this part, and perhaps a concerted consideration of the club-sport reinforcement part, and a write-up on what it takes to install? I still have most of the broken part to examine. I would want to make sure the reinforcement actually added support where the fracture occurred...
*The information was delivered unofficially, delivered by word-of-mouth only, for free as a kind and generous professional courtesy. They can make this information available in a formal detailed official engineering report, for a time, if it is paid for, and it is not likely to be cheap. This is because an official report exposes the testing company to time spent later, in involvement in any business or legal proceeding in which the report might become material.
HTH,
Joe
They were not told, but from their tests they were able to identify the metal as from Porsche, because it is apparently a proprietary aluminum alloy that is very strong. I would guess that any shop that ever simply tries to weld one of these back together would be fighting a metallurgical battle they couldn't win.
They found that my part had two fracture surfaces, meaning that a crack had occurred much prior to the date of my road incident, and the complete failure was induced by enough new jolting to break the rest of it. It seems we should define a regular inspection protocol for this part, and perhaps a concerted consideration of the club-sport reinforcement part, and a write-up on what it takes to install? I still have most of the broken part to examine. I would want to make sure the reinforcement actually added support where the fracture occurred...
*The information was delivered unofficially, delivered by word-of-mouth only, for free as a kind and generous professional courtesy. They can make this information available in a formal detailed official engineering report, for a time, if it is paid for, and it is not likely to be cheap. This is because an official report exposes the testing company to time spent later, in involvement in any business or legal proceeding in which the report might become material.
HTH,
Joe
Extremely interesting, and thank you for doing this for the community, Joe.
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Joined: Feb 2014
Posts: 3,311
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From: Colorado Springs
I was able to get the part examined (thoroughly but 'unofficially'*) by a metals lab, and there were some aspects of interest.
They were not told, but from their tests they were able to identify the metal as from Porsche, because it is apparently a proprietary aluminum alloy that is very strong. I would guess that any shop that ever simply tries to weld one of these back together would be fighting a metallurgical battle they couldn't win.
They found that my part had two fracture surfaces, meaning that a crack had occurred much prior to the date of my road incident, and the complete failure was induced by enough new jolting to break the rest of it. It seems we should define a regular inspection protocol for this part, and perhaps a concerted consideration of the club-sport reinforcement part, and a write-up on what it takes to install? I still have most of the broken part to examine. I would want to make sure the reinforcement actually added support where the fracture occurred...
*The information was delivered unofficially, delivered by word-of-mouth only, for free as a kind and generous professional courtesy. They can make this information available in a formal detailed official engineering report, for a time, if it is paid for, and it is not likely to be cheap. This is because an official report exposes the testing company to time spent later, in involvement in any business or legal proceeding in which the report might become material.
HTH,
Joe
They were not told, but from their tests they were able to identify the metal as from Porsche, because it is apparently a proprietary aluminum alloy that is very strong. I would guess that any shop that ever simply tries to weld one of these back together would be fighting a metallurgical battle they couldn't win.
They found that my part had two fracture surfaces, meaning that a crack had occurred much prior to the date of my road incident, and the complete failure was induced by enough new jolting to break the rest of it. It seems we should define a regular inspection protocol for this part, and perhaps a concerted consideration of the club-sport reinforcement part, and a write-up on what it takes to install? I still have most of the broken part to examine. I would want to make sure the reinforcement actually added support where the fracture occurred...
*The information was delivered unofficially, delivered by word-of-mouth only, for free as a kind and generous professional courtesy. They can make this information available in a formal detailed official engineering report, for a time, if it is paid for, and it is not likely to be cheap. This is because an official report exposes the testing company to time spent later, in involvement in any business or legal proceeding in which the report might become material.
HTH,
Joe
So, what was the unofficial failure mode of the original crack?
Three Wheelin'
Joined: Oct 2003
Posts: 1,489
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As I recall, the implication was that it was also impact-originating, as opposed to any gaps/imperfections in the metal. I cannot think of any prior impact though... Bumpy roads at worst. No air, no track days, so no corner kerbs etc.
Burning Brakes
Joined: Sep 2008
Posts: 910
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From: Northeast
Another thank you for all you have posted about this. Was your car ever driven by anyone else that could have contributed to the problem?
Three Wheelin'
Joined: Oct 2003
Posts: 1,489
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25 miles on it at delivery, and only left at the dealer once for an oil change at 1100 miles. Neglected to check the in/out miles for that visit (not yet that paranoid)
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Joined: Feb 2007
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From: ^ The Bay Bridge
Still, there are a lot of cars out there running with no problem at all. So it seems to be a freak occurrence, or near freak occurrence—but it would be wonderful to understand this better. We may never get there, but your work and the work of others has shed some invaluable light on the incident with your car. Good to hear the piece is made of super strong material, still wondering whether the analysis company can tell us more, politely and off the record (is it brittle? is it a good use of said material? etc) in its opinion. Wonder if the first impact even happened in some aspect of the shipping/delivery.
Instructor
Joined: Apr 2014
Posts: 156
Likes: 9
Aren't the cars driven on and off the RO-RO vessels? In my shipping experiences, while complaining about the cost of some crates, an export packer once told me, "A stevedore could tear up a bowling ball with a cigarette paper."