oh My GOSH!!! Listen to yourselves! Everyone's suddenly a self-appointed expert. I can't believe the misinformation being bandied about in this and other recent threads on this subject.
While I'm sympathetic to the OP's situation, and can certainly understand his panicked concern about the car given all the misinformation and hyperventilating he has read on this forum, I think everyone should take a very deep breath before leaping off this particular cliff.So in the opinion of these welders, whose qualifications have not been revealed, a decision is reached to take the car out of service and initiate litigation against a major multinational corporation? On what basis do you think these welders know enough about the structural load paths in the R8 to reach a valid conclusion on the matter?I've spoken to several welders regarding this issue. They have told me they are aware of this issue on R8's and some A8's. Even with no accidents involved. I asked, in their opinion is this a DANGEROUS CONDITION?. They advised me that it was very dangerous and to not drive the car further.
I am not personally aware of ANY chassis failure, either total collapse or significant distortion, subsequent to and attributable to this sort of minor cracking at the shock mount. If there has been a documented failure we'd all appreciate hearing about it.The subsequent discussion then branches off into mostly uninformed speculation about adhesive bonding.My welder assumed is was 7 series alloy based on his research, and as he was an airframe mechanic it didn't present him with a problem. What type of Aluminium is used in cars? The most widely used alloy is 7075. It consists of aluminium, zinc, magnesium and copper. It's the strongest of all aluminium alloys and comparable in that respect with steel, however it weighs only a third of what steel weighs. As an aside, a lot of specialist regard 7075 as unweldable !!!!!!!!
This kind of "expert talk", which is not DIRECTLY applicable to the topic at hand, just serves to mislead the already ill-informed. Please stop doing it.
The FACT is that the Audi structural repair manual for the R8 specifies EXACTLY the welding procedures and composition of the the filler metals which may be used in repairing the R8 frame. It also specifies EXACTLY which adhesive bonding procedures and blind riveting procedures are approved, and where they may be used.
It is good to be conservative and concerned, but please do so on the basis of knowledge gleaned from the truly informed, not opinions found on this or any other internet forum. I wish you the best result as you work your way through your concerns.