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Old February 19th 07, 06:54 PM posted to rec.skiing.alpine
VtSkier
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Posts: 1,233
Default Can I set my own bindings?

down_hill wrote:
Walt wrote:


Think of it this way: I'm testing a binding. I place a boot in the
binding and apply a torque of, say, 50 Newton Meters. The binding
doesn't release. I've just described a situation where there is
torque but no motion. Do you say there is no torque here? If so, how
does one ever test a binding?



What are the springs doing? Are they not being compressed motion? I
was trying to think of a torque but no motion example but it seems to
depend where you measure something. If you take a dragster with
automatic transmissions on the start line, engine loaded brakes locked
would be my example. If you look at whole picture it fits statement if
you look at componets it fails.


In the binding:

The springs are providing a force to oppose the preset
release setting until the force needed to release the
binding has been reached. At which point there will
be torque because motion has been added to the force.

In some (most, I hope) bindings, the springs will compress
to provide "flexibility" and a return to center when
release potential is reached but only momentarily
and I guess that torque is produced in this
scenario because there certainly is motion, but
to that point at which the motion begins, you
have only applied force or potential torque to
the binding, and the torque wrench will measure
the point at which that motion begins.

In the dragster:

Because the parts in the engine are moving, there is
torque. This is a measure of work. Because you are
not allowing the dragster to move, this torque is
being dissipated as heat in the transmission until
you dump the brakes when it will be sent immediately
to the drive wheels.

In the dragster as whole, the engine is producing
torque because the engine parts are moving. This
torque is sent as force to the transmission and
drive wheels which converts this force to work
(moving down the drag strip).

In terms of the dragster, the work is "potential"
until you dump the brakes. Potential work is
only force.

The brakes are not loaded, the transmission is. The brakes are
simply allowing the transmission to be loaded.

An automatic transmission can be visualized as two fans,
one driven by an engine and one to drive a set of
rear wheels, opposing each other in a fluid (transmission
fluid).

Now simplify this.
Take a motorized fan and opposite to this place a pinwheel.
If you start up the fan, the pinwheel will accelerate to
the speed of the fan just very slightly slower than the
driven fan.

Now hold the pinwheel in place with you hand (brake) until
the driven fan is up to speed. The pinwheel will accelerate
to the speed of the driven fan in the blink of an eye.

This is what the dragster is doing for maximum acceleration,
the skill comes from the driver knowing when the drive
wheels will break loose and acceleration will be compromised.

A car is too complex a machine to use as an example of
just one thing or concept because a whole lot of things
are happening at the same time.
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