For those who got lost in the confusion,
the Load on the Gin Pole is the sum of the
LOAD on one side and the PULL on the other.
When there is a single pulley, the load on the
Gin Pole is 2X the LOAD plus friction loss.
(The downward tension in the Pull rope equals
the downward tension in the Load rope + friction).
When a Block and Tackle is between the Gin Pole
and Load, the load on the Gin pole is the Load
plus the Load divided by the mechanical advantage
(i.e. the Pull force). The B&T lowers to total load
on the Gin Pole for THIS configuration. For a
mechanical advantage of 2:1, the load on the
gin pole is 1 + 1/2 = 1.5X load plus friction.
When a block and tackle is between the Puller
and the Gin Pole rope (single pulley), the puller
gets a benefit from the block and tackle, but the
load on the Gin Pole is the same as if no B&T
were used, i.e. 2X the Load plus friction losses.
I hope we can move on to another thread now :-)
At least this was an interesting respite from
heart valve research / selection / surgery...
Tom N4KG
On Thu, 14 Jun 2001 KB7WW Art Moe <kb7ww@uswest.net> writes:
>
>
> Mike Gilmer - N2MG wrote:
> >
> > On Thu, 14 June 2001, n4kg@juno.com wrote:
> >
> > > ...and the argument proposed by some here that a
> > > mechanical advantage between the puller and a
> > > standard single pulley on the gin pole provides a
> > > load readuction for the gin pole is
> > > FALSE.
> >
> > I don't recall reading anything in which the author advocated
> arranging the mechanical advantage between the worker and the
> ginpole.
> >
> > I don't see why anyone would *want* to set it up this way - the
> workers gets an advantage, but the ginpole does not. Putting the
> mechanical advantage between the ginpole and the load is where it
> belongs - both the worker AND the ginpole "gain".
> >
> > 73 Mike N2MG
> >
>
>
> Where is the advantage for the gin pole??????? If the section
> weighs a hundred
> pounds, I don't care how many pulleys you use there is still a
> hundred pounds
> on the gin pole.......... It will take less pull to raise because of
> the
> mechanical advantage, but there is still 100 lb on the gin pole....
>
> Art
>
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