I built my own and it works very well.
I'll try to put up a photo of the head, but essentially it is a end cap for
the steel pipe I used for the pole.
I found several caps that would work, some I had to cut out the center and
others were already open. I welded to arms about 8 to 10 inches long to
this. The arms are parallel and have the pulley mounted between the arms. I
used a bolt through the end of the arms as a tie point.
As I was lifting 45 G and some heavy antennas I used a multiple pulley
arrangement to gain a mechanical advantage which allowed one person on the
rope to easily lift well over 100#.
The head easily pivots so that when they pulled a section of tower up to me,
I could easily swing it around over the sections already installed and then
lower it into place.
First I have to find the photos which in this case I think are scans so they
may be a tad difficult to find. But I'll look for them tonight. If I find
one that shows the top I'll put it up, or maybe I should just go out to the
shop and shoot a photo with the digital camera and make things simple.
73
Roger Halstead (K8RI, EN73 & ARRL Life Member)
N833R, World's Oldest Debonair (S# CD-2)
www.rogerhalstead.com
Looking through the archives I've found little on the specific topic of gin
pole heads (I call them pulleys, but WB0W has them listed as "heads").
One idea I got was to use some a pulley from a marine supply store. These
pulleys are rated for around 1000 puonds of working force and have breaking
forces in the 3000 pound range-- sufficiently strong enough to handle the
Rohn 25G that I want to put up...
One problem I've run into is a good way to mount the marine pulley to the
pole itself. It appears WB0W's pole head has a build-on clamp that slides
on top of the pole. Any alternatives out there? If you feel this is not a
good/safe idea, I'd like to hear from you as well.
Thanks,
Jason
KB5URQ
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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