Tony, I agree that the bending moment is reduced and the tension is
increased. The stock shaft has a flat for the D washer and probably standard
profile threads. I am guessing this might be the failure point. The uprated
axle we are working on would have higher strength and a J form thread for
fatigue life enhancemant. I would prefer to eliminate the flat also. Looking
for input from any and all, we don't want any catastrophic failures! Kas?
Mark
72 TR6
----- Original Message -----
From: "Tony Drews" <tony@tonydrews.com>
To: <FOT@autox.team.net>
Cc: <fot@autox.team.net>
Sent: Friday, September 05, 2003 1:55 PM
Subject: Re: Fix for TR brakes
> Scott, that's a VERY interesting question! Thinking through how this
> works, I'm reasoning that it may actually make it less likely to break off
> the stub axle. I hope I'm right since I'm running a set of these and I
> already rolled one car at Road America... (where I'm going in a couple of
> weeks) Please correct me if I'm wrong - here goes my analysis of why this
> works...
> The inner wheel bearing inner race butts up against the upright that the
> stub axle bolts through.
> The new part butts up against the inner wheel bearing inner race as well
as
> up against the outer wheel bearing inner race.
> What this should do is take some of the forces normally applied to the
stub
> axle and transfer them to the upright through the very hard inner bearing
> inner race.
> This will increase the tension forces on the stub axle but decrease the
> bending moment that the axle sees. I strongly suspect that the bending
> forces are much more likely to break the stub axle than tension forces
are.
> What I have found is that if I run the bearings with a bit of preload, all
> of the deflection disappears. If I put the couple of thousanths of free
> play that I'm more comfortable with there's some deflection but it's
better
> than it was.
>
> - Tony Drews
>
> At 09:39 AM 9/5/2003, Barr, Scott wrote:
> >Any chance stiffening the stub axle in this way moves the forces around
in a
> >way which might cause them to start breaking off?
> >
> >Scott
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