Dave, why are u still struggling with this? Barney's explanation
is well founded on engineering principles, and its a lot more
complicated and interesting than the drill chuck metaphor.
Mike L.
60A,67E,59Bug
----- Original Message -----
From: David Pennington <racerx23@earthlink.net>
To: <mgs@autox.team.net>; Barrie Robinson <barrier@bconnex.net>
Sent: December 29, 2000 12:58 PM
Subject: Re: wheel hubs on the "wrong" side
> Barrie,
> Thanks for the note. Please let me be clear, I do believe in the
mysterious
> locking action of the stock setup. Sufficient examples have been
presented,
> with but one counterexample (perhaps) under investigation. I
don't yet
> understand why it works, but the number of theories I have seen
leads me to
> conclude that I'm not alone in this. Your theory is one I have
heard, but I
> don't think it stands to reason. I will attempt to explain my
thinking on
> this.
>
> Looking at the left rear wheel, (it has a RH thread) imagine the
car doing a
> fast accelleration. During the accelleration, your theory would
be working,
> the shaft would be trying to screw itself into the spinner.
However, during
> braking (which is a sharper accelleration curve by far) the
reverse would be
> enacted. Just like your drill example. Imagine the wheel,
spinning rapidly
> (counterclockwise). Suddenly the shaft/wheel stops. The nut/hub
will at that
> point try to keep spinning counterclockwise, which with a RH
thread of course
> unscrews it. Since this twisting force force during braking is
much greater
> than during accelleration, the net effect would be the reverse
of the desired
> effect, so this theory cannot be what is causing the spinner to
tighten. We
> have to look elsewhere for the mysterious locking force.
>
> that's my 2 cents anyway
>
> - Dave
>
>
> ----- Original Message -----
> From: Barrie Robinson
> To: David Pennington ; mgs@autox.team.net
> Sent: Friday, December 29, 2000 1:29 PM
> Subject: Re: wheel hubs on the "wrong" side
>
>
> David,
>
> We all know that we are talking splined wheels not bolt on
wheels. yes?
>
> It is all very simple if you have engineering
training.....Image the wire
> wheel and its wing nut.. The wing nut is reluctant to rotate
(Newtons's
> first law of motion). As the half/stub axle rotates it screws
itself into
> the wing nut because the nut is resisting movement This
screwing-into or
> tightning continues as the nut always resists being moved.
Conversely when
> the car drives backwards there is a tendancy for the winged
nut to unscrew.
> The force applies is not large as one can imagine - but given
time it will
> get loose and then will unscrew rapidly. If you want to see
this work just
> put a bolt in your electric drill, put a nut on the end and
see what
> happens when you turn the drill on - in both directions.
>
>
>
> At 01:17 PM 12/28/00 -0500, David Pennington wrote:
> >I am not trying to be obstinate, but why would a spinner get
tighter from
> >driving the car forward as opposed to backward? Stopping and
starting
> torques
> >have been discussed. My experience has been that stock
spinners tend to
> >gradually loosen with use. I also know from experience the
stock setup can
> and
> >will unscrew if the splines fail, and I have proposed a
theory as to why
> they
> >do so. But what possible force could be twisting the spinner
if the
> splines
> >are not spun? Am I missing something here?
> >
> >I can imagine a tiny amount of play may exist between the
splines which
> could
> >allow the wheel to twist the spinner, and this
could/would/will eventually
> >loosen the spinner. But this play would be exceedingly small
with good
> >splines, if it exists at all. And if it does exist, it will
tend to undo
> ANY
> >spinner, regardless of its LH-RH thread type. This is why ALL
spinners
> need to
> >be checked periodically. BTW, a fine thread spinner is less
subject to
> >loosening than the coarse, due to the increased force the
fine thread
> spinner
> >applies to the wheel if both are equally torqued. This
explains the switch
> >from 8 TPI spinners to 12 TPI spinners found on later models.
> >
> >I don't follow your reasoning here, and would very much like
to understand
> if
> >there is a mechanical principle I am overlooking.
> >
> >thanks again,
> >
> >Dave P
> >70B
> >
> >----- Original Message -----
> > From: Dave Quirt
> >
> > David:
> >
> > Don't do it. To do so is a definite death-wish. The main
draw-back is
> > that extended reversing WILL eventually unscrew the
hub-nuts when they
> > are on their proper side - they tighten (or keep tight)
during forward
> > motion. If put on the wrong side, they will be reversing
whenever you
> > are moving forward. Get the picture now??
> >
> > Dave Q.
> > As and Bs
> >
> >
>
>
> Regards
> Barrie Robinson
> barrier@bconnex.net
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