Dw,
I like it, I like it!! But the one problem I have is that the curved
sufaces are between wheel and axle. The surfaces of the nut and wheel are
dead straight and slim. It may be that the wheel tightens onto the axle
but why would the nut cosy up to the axle as well? If you imagine the
wheel and nut ever-so-slightly loose with several thous between them then
one could imagine the wheel being forced up onto the curve of the axle (?)
BUT this leaves the nut (which was not touching the wheel) sitting limply
on the thread of the axle. So unless the nut is somehow sucked up by the
wheel there is nothing to tighten it - except good old Newton's Law of course!
At 01:38 PM 12/29/00 -0600, you wrote:
>I am new to this list, but I have been on the triumphs list for some time.
>Interestingly, I just read an explanation that may address this area.
>(unfortunately, I deleted the original e-mail but saved that text to a
>column I edit for our British Cars of NH (USA) newsletter.
>'67 TR4A, '72 XJ6 & '74 MGB
>Dave
>
>ps Credit given below:
>
>"What causes the knockoff to tighten instead of loosen is the same
>principle that allows a train to go around a curve.
> Picture in your mind a cross section of railroad track, and the wheel on a
>train car. (Remember, the wheels on a train are part of the axle.... the
>'inside' wheel turns at the same rate as the 'outside' wheel). Thus, when a
>train car goes around a curve the inside wheel is turning the same rate as
>the outside wheel. Which means(!!), one of the wheels must be
>sliding/skidding on the track because you have a different radius for the
>inside track and the outside track. SO, how does the train go around a
>curve?
> The top of the track is curved and the wheel surface is slightly slanted
>(larger diameter on the inside of the wheel and smaller diameter on the
>outside of the wheel). As the train goes into a (for example) left curve,
>centrifugal force pushes the train axle(and wheels) to the outside of the
>curve. The outside of the "left wheel" is in contact with the "lower" edge
>of the track and the inside of the "right wheel" is in contact with the
>"center" edge of the track. This results in a slight increase in the
>mathematical radius of the inside wheel and decrease in the mathematical
>radius of the outside wheel, which makes the radius for inner and outer
>wheels nearly the same, which allows BOTH wheels to "roll" on the track
>rather than slide.
> If your still with me, if you haven't fallen asleep and your eyes glazed
>over (!!!!!), the same basic thing is happening between the knockoff and
>the "knockoff mating surface" of the wheel. They are both slightly curved,
>thus as the axle rotates with the knockoff on the axle and tight against
>the mating surface on the wheel, there is just enough difference in radius'
>to effectively be constantly tightening the knockoff.
> DON'T EVER REVERSE THEM!! (Left on right and right on left)!"
>Edward
>fogbro1@home.com
>
>
>
>
>
>"David Pennington" <racerx23@earthlink.net>@autox.team.net on 12/29/2000
>12:58:08 PM
>
>Please respond to "David Pennington" <racerx23@earthlink.net>
>
>Sent by: owner-mgs@autox.team.net
>
>
>To: <mgs@autox.team.net>, "Barrie Robinson" <barrier@bconnex.net>
>cc:
>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
>
>
Regards
Barrie Robinson
barrier@bconnex.net
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