Ball joint extenders, was Re: need beta testers (tie-rod relocation)

[Dan Bubb" <jdbubb@ix.netcom.com (Dan Bubb)]

>From the Frankentruk website:
"So far it's been 20,000+ miles with no problems (but then, last time I
wrote this kind of thing it was about the balljoint extenders and they broke
a week later!). "

I have all sorts of reservations about these ball joint extenders, from the
strength of the extender itself , but primarily the strength of the hub
carrier where the ball joint (or extender) is secured.
The extender will create resisting forces in the hub carrier that are 2 to 3
times what it will see with a normal ball joint installation.
I've kept my mouth shut so far for one reason;
It's impossible to calculate the forces in the hub carrier without doing
finite element analysis since it has very complex geometry. It's impossible
even to do a reasonable simplified representation of it to give an order of
magnitude of the stresses. So, I cannot say at what point this is DEFINITELY
a hazard.

In any event, if you plan on installing ball joint extenders, plan on
inspecting them for cracks or deformation weekly. Definitely inspect and
perhaps even remove and magniflux them before and after any track day or
extended hard driving. Same goes for the hub carrier!
This isn't a joking matter! This modification will significantly increase
the stresses in a critcal area that is already high stress. If your lower
ball joint seperates from the hub carrier there will be extensive damage to
your car and perhaps worse!

As much as this seems like a wonderful modification to improve handling, I
will not be doing it!
Dan


----- Original Message -----
From: "T Berk" <tberk@mindspring.com>
Cc: "Scirocco List" <scirocco-l@scirocco.org>
Sent: Friday, April 25, 2003 8:22 AM
Subject: Re: need beta testers (tie-rod relocation)


>
> > So, where'd it go???
> > Dan B.
> >
>
> > Dan Bubb wrote:
> >
> > Fascinating!
> > This link was in the e-mail you responded to right below "check out
> > this link":
> >
> > <http://www.ghiagirl.com/phrankentruk/balljoints_table.htm>
> >
>
> Intuitive Mechanical Design hat upon my head.
>
> I'm somewhat concerned about the 'neck' aspect of the ball joint
> extender. I would want it butt up against the hub like the current
> control arm does. Hmmmm, I'll have to go out and study the ball joint
> contraption again. Looks spindly though.  Also I agree a stepped
> cylinder is not optimal.
>
> (In fact on the 'lowered car correction via raised struts' page is
> mention of a remorseful acknowledgment of broken parts after claiming
> no problems beyond 20K miles). <jinx>   btw- Wood as a suspension
> component. Hmmmm.
>
>
> More later,
> TBerk
>
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