Dave:
Don't you have a couple of words reversed here?
<<<snip>>>
> 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.
<<<snip>>>
If a set of rail tracks is bending to the engineer's left, the left
hand rail is shorter than the right. That means the left wheel has
less distance to travel. By designing the taper to the wheels, the
left wheel (when it slides to the outside of the curve) travels less
distance than the right for each rotation. It is in effect, smaller
than the right which means its radius at that time is also smaller
than the right: C=2*pi*r.
Shouldn't your last sentence read: "This results in a slight DECREASE
in the PHYSICAL radius of the inside wheel and INCREASE in the
PHYSICAL radius of the outside wheel." END OF SENTENCE. Inside being
the wheel on the inside of the turn and for the example the left
wheel(s).
HO and Lionel model trains use the same principle. In fact, because
the tracks curve more sharply (scale wise) for Lionels, the taper on
the wheel's "tire" is quite obvious.
Also, isn't this why dirt track racers using locked differentials have
stager in the setup with the outside tire larger in diameter (and
therefor radius) than the inner?
Blake
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