[Top] [All Lists]

[Towertalk] ginpole redux

To: <>
Subject: [Towertalk] ginpole redux
From: (Chris BONDE)
Date: Fri, 12 Jul 2002 13:31:50 -0700
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.
>Self Supporting Towers, Wireless Weather Stations, see web site: 
>Call 888-333-9041 to place your order, mention you saw this ad and take an 
>additional 5 percent off
>any weather station price.
>Towertalk mailing list

<Prev in Thread] Current Thread [Next in Thread>