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Back on the Cobra-
I looked at some more detailed pictures and found even more things that I would not consider particularly great ideas. It looks like a fair amount of those aluminum frame bits are bolted together... bolted joints are inherently not the greatest means of joining chassis bits- this is why aluminum monocoque racers, like the 956/962, are riveted together, like airplanes. Bolted joints can fail in a multitude of ways, and add to an already lacking torsional rigidity. But, if done properly, can still function at a high level- airplane bulkheads made of aluminum or titanium are bolted together.. right?
The main flaw here is that the Cobra's structures- where bolted together- are tapped holes. Tapped aluminum holes. Wherever bolted joints through aluminum are used on jet aircraft, the holes are through holes, and tight tolerance, self locking NAS hardware is used. This Cobra is designed with socket head cap screws torquing into tapped aluminum holes. Socket head cap screws do not have nearly the tight tolerances that NAS hardware has- thus attributing to more compliance - again with the rigidity. And also, they are not able to be torqued to apply a high amount of preload- necessary to press the surfaces together tightly and use clamp loading to lessen compliance in the fixtures. Because they are threading into aluminum. Where a non-locking nut or, in this case, no nut is used, then it is imperative that at least the bolts are head-drilled and safety wired together to prevent them from backing out due to vibration- vibration that this Cobra will surely be producing.
Again, it's a wonderfully machined work of art, but not a performance engineered machine. I need not get into how Solidworks is not a suspension parameter design tool, either...
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