This is basically what I mentioned in my first post. If you have 2 pulleys
at the top and fix the rpoe on the load pulley you ccan reduce the lifting
force require to about 1/3 of the weight.
I have never seen a ginpole up close. Why cannot you put 2 pulleys
there? Even putting a rope through the one pulley, making a very short
loop out of it into which place the hook of the 2 pulley block then go
ahead. Or use the pulley on the pole but put a separte pulley on the mast
for the down swing of the rope, as long as the fixed to load rope comes to
the pulley on the gin pole should work.
O O
| | / \
| | / \
L O Pull
oad "
THe load pulley as the fixed attachment. This should give the down pull 1/3
of the load, count the ropes supporting the load 3.
Chris opr VE7HCB
At 03:33 AM 2002-07-12 -0400, jljarvis wrote:
>kk1l observed that I wasn't thinking clearly, with
>respect to possible pulley scenarios and ginpole loads.
>It IS possible to reduce the load on the pole, by using
>a 2 part tackle on the LOAD side of the ginpole:
>
> >
> > O T fixed to top of pole 150# total
> > | | |
> > | | |
> > | | |
> > | O
> > | V
> > | LOAD 100#
> > |
> > |
> > V
> > 50#
>
>Now comes the question...anybody see a way to actually RIG a
>pole like that? The rohn top casting/block doesn't provide
>an easy way. A through-bolt would get in the way of the
>LIFT line, in the pole. The fixed line, at 't', would have to
>be fastened to a clamp of some sort.
>
>Jim/N2EA
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