>, but it
>needs to be only half as strong as the rope without the second
>pulley.
>
The mechanical handbooks say that the rope needs to rated for the
full load. Under static conditions there is no problem, but
dynamically the full load could be applied to the rope. Also,
it's the safe way. A pulley could stick, or the load could slip
and drop a ways, etc.
The pull rope can come from the top, as all the previous
discussion has indicated, or the bottom pulley. The tower man
can do the pulling from the top. This is possible with the
mechanical advantage lowering the pull required. The load on the
gin pole in this case is the load weight minus the pull rope
tension.
All this is interesting, but I think the best way is with a
motorized winch or a tractor which can hold the load in place.
George
W2VJN
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