Structural Foam for chassis stiffening

myduster360 said
wow,,,,,I'll try to be less verbose.

I've spent weeks being trained in using FEA and CFD software and use it regularly. I'm well aware of the caveats. All tests started with FEA but I believe at least 2 of them validated their model with bodies in white.

The mazda beam was tested such that increased "adhesion strength" in the shear plane improved performance. This was because they were mostly focusing on improving crash performance. While I agree that it's a significant factor, I'm not so sure a benefit can't be had without the perfect bonding surface.

Have a little more open mind,,,,containing the foam to a finite area is as simple as a child's balloon:

Measuring torsional rigidity is not over complicated. A simple Before/After comparison is more than most vendors provide. Was USCT simplistic "look at the tape sag" equally scrutinized?

Hey, if you want to have a bullet point presentation that overly simplifies the issue and doesn't address all the possible complications then become a politician. If you want to have a real engineering discussion you'll have to do some reading. At least that's how it worked when I got my bachelor's in Aerospace engineering from UCLA. Maybe it's all youtube videos and bullet points now, I dunno.

Yeah, the GM and Chrysler tests both verified with bodies in white. But they were pulling brand new chassis' off the assembly line. The Mazda tests shows that if you have less than spectacular adhesion, you will get less than spectacular improvements. That is a VERY real consideration given your application and method. Successful engineering is all about making sure your methods match your application and you're not assuming things in the math that aren't happening in real life.

Want it short and sweet? It would be faster, easier, and much more likely to be successful if you just spent an hour with a MIG welder and stitch or seam welded the corners of the chassis you intend to fill with foam. That will absolutely stiffen the chassis, would require no extra tools or skills that most of us don't have already, and could just as easily be verified.

And no, I don't give the USCT tests any more credit. I scrutinize the heck out of any test that's carried out by the same folks that are selling the product they're testing.

Like I said, knock yourself out. For my time and money I'd do some stitch welding. The factories don't do that because of cost, the foam is a cheaper way for them to operate compared to welding.