RE: [DML] Re: Checked my TABs.... AARG!!

[<rob@xxxxxxxxxxx>]

David,

If money was no object and you're willing to live with a harsher ride via an
all metal Heim joint as per race car practice then you might consider it. It
would probably require completely redesigned trailing arms (ala Pierce
Design but stock frame compatible)and be rather cost prohibitive. I think an
incremental approach by double-nut retention, stronger bolts, washers, and
perhaps even bushings (also expensive) would suffice. The first three items
combined with careful installation and torqueing would eliminate the vast
majority of failures at a much more reasonable cost compared to custom
(bespoke as they'd say in the U.K.) designed trailing arms.

Rob Grady,

P.J.Grady Inc.

-----Original Message-----
From: dmcnews@xxxxxxxxxxxxxxx [mailto:dmcnews@xxxxxxxxxxxxxxx] On Behalf Of
David Teitelbaum
Sent: Wednesday, March 15, 2006 1:02 PM
To: dmcnews@xxxxxxxxxxxxxxx
Subject: [DML] Re: Checked my TABs.... AARG!!

The hardness of the shims is also a problem. Another problem is the
spacer inside the bushing. It can collapse especially if you
overtorque the TAB. The whole set-up is a problematic area. It is not
compliant enough as the trailing arm  moves up and down and tries to
twist the joint in another plane. The ultimate would be to design a
retro-fit Heim Joint in there. It could take the bending stresses off
of the TAB. I believe it is the bending stresses that are the real
culprit. Bending the bolt back and forth under the tensile stress is
what is really stretching  the bolt. Do that for a while and we see
what the result is. The "trick" is to tighten the TAB enough to put it
under enough stress so that the stress from it's induced loads  cannot
exceed the tensile stress from  torqueing it. The problem is if you
are not careful you can ovetorque it and collapse the spacer inside
the bushing. A fine line. That's why I think the Heim Joint is the way
to go, not further trying to Band-Aid the TAB joint. Sometimes you
have to look at the big picture, trying to improve the origional joint
may seem like the easy way to go but it cannot solve the bending loads.
David Teitelbaum
vin 10757 




--- In dmcnews@xxxxxxxxxxxxxxx, <rob@...> wrote:
>
> Toby,
> 
> Another point you might consider Toby is to have some harder spacer
washers
> made and supply them with your kit as you may not be aware of how
soft they
> are. When I last checked a few years ago as I recall their hardness
is about
> 22 C-scale. As I'm sure you do know that is basically cold rolled u







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