David,
The vast majority of motion is forwards so that the nut tightens most of
the time. Sudden braking will loosen it ever so little but subsequent
forward motion will tighten it up again. If all you did was braking (how
do you do that?) then the nut would fall off. Remember the warning not to
tow ww cars backwards- well, what you must remember as well is that the
wheels come off only after towing it for some considerable kilometres
(miles). It is the sum of the forces that dictate whether the nut tightens
or loosens SIGNIFICANTLY - and you must stop just picking on one moment in
time when braking does exert a brief loosening effect - and obviously the
biggest by far sum is those generated by the forward motion - one has to
presume that the cars go forward more than they do backwards? Best way to
describe it I suppose is to think of little elves pushing on the nut faces,
thus the turning of the screw (oh I love it - a joke!) takes a while. Now
that explains it - Shakespearian elves!
At 12:58 PM 12/29/00 -0500, you wrote:
> Barrie, 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
> The wing nut is reluctant to rotate (Newtons's
> As the half/stub axle rotates it screws itself into
> This screwing-into or
> 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
> 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
>
>
>
>
Regards
Barrie Robinson
barrier@bconnex.net
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