Strut Tower Brace Design Revisited

[Peter Schulz]

Bernie:

Sorry, but your design is engineered no more or less than Georges....
Bottom line is that we all have our opinions - in the absence of the real 
science of suspension design with force measurements and analysis

"If your rational were true, my strut brace designed for compression forces 
only, would have hammered itself to pieces by now, under your osculating 
tensile forces.  Rather, it shows no sign of the tubing ever leaving the 
jam nuts, the design intent."

What does that mean in respect to the road environment where you live?  If 
your roads are relatively smooth, you would likely see alot less strain 
then on uneven, poorly maintained roads.

-Peter


At 03:38 PM 2/28/2005, Bernie Benz wrote:


> > From: George Sidman <sidman at montereynet.net>
> > Date: Mon, 28 Feb 2005 10:28:56 -0800
> > To: 200q20v at audifans.com
> > Subject: Re: Strut Tower Brace Design Revisited
> >
> > Bernie:     It appears there is some confusion and/or
> > disagreement surrounding what the tower is doing, what the
> > strut is doing, how they share dampening through the rubber,
> > etc. Bottom line is, your idea to tie the strut tops
> > together does produce beneficial results, to which a number
> > of us can gratefully attest.
> >
> > My point is that the loading on the brace is dynamic, not
> > static, and the generally accepted physics principal that
> > for every action there is an equal and opposite reaction
> > tells me that the strut cannot be loaded without there being
> > an unloading moment. In other words, pressure pushing the
> > towers apart. That back and forth movement, however slight,
> > is what introduces metal fatigue. The solidly connected bar
> > prevents that for the strut, and helps reduce the effect of
> > whatever the springs are doing to the towers. I am hoping
> > that the solid brace reduces those stresses enough to keep
> > the wheels parallel and the towers from getting romantic.
> > And it all appears to work.
>Believe what you wish, George.  I responded only to allow others to consider
>differing logic, such that they might not be led down your primrose path.
>
>If your rational were true, my strut brace designed for compression forces
>only, would have hammered itself to pieces by now, under your osculating
>tensile forces.  Rather, it shows no sign of the tubing ever leaving the jam
>nuts, the design intent.
> >
> > Cost wise - total was $110, and a bargain for what it does.
> > Weight wise - I could diet for a few days and make up the
> > difference.
>10 or 20X the weight of a an engineered design.
> >
> > Clearly, there is no definitive answer, short of dusting of
> > my long forgotten structural engineering books and working
> > out the numbers.
>Stick to your CEOing, George.
> > Anyway, we do this because it's fun and how else do we entertain
> > list members?
>We should be paid for the comedy value.
>
>Regards,  Bernie
> > --
> > GEORGE SIDMAN, Chairman
> > sidman at webloq.com
> > Monterey, California
> > 831 760-0168
> > _______________________________________________
> > 200q20v mailing list  http://www.audifans.com/mailman/listinfo/200q20v
>
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Chelmsford Ma, USA