In a message dated 12/19/2006 12:53:29 P.M. Pacific Standard Time,
towertalk-request@contesting.com writes:
> Now, a final question: should I use wire rope clips or a guy grip to form
the end that will connect to the tower? Seems to me a guy grip would be
best, but I want to make sure it can be used on non-EHS cable.
You can't use a grip because it's too long and will interfere with your
pulley going up the tram line up at the top of the tower. You want the
tramline
pulley to end up right next to the tower or mast. A thimble and couple of
cable clamps will suffice.
You can't use an EHS grip on non-EHS cable either.
> I'll use a Klein grip and come-along at the bottom end.
Yep. I always back up the Klein with a cable clamp (clamping the comealong
line and the tramline together) as a redundant safety measure in case the
Klein grip slips. And sometimes they will slip.
> That'll still be
3-strand 7/16" nylon, and my impression is that nearly everyone uses some
sort of rope for the pull line. Wouldn't want that to break, either.
I don't like rope for tramlines since there's too much stretch
involved. Use a wire rope cable. Most of the previous posts have included good
info so you should be good to go.
The force at the bottom of the rope - and 7/16" is plenty - pulling
a 100# antenna up is 200#. That's 100# of load up to the pulley at the top
and 100# coming down the other side. Of course it's a little different for the
vectors of the tramline as Eric has pointed out but the force isn't 100#.
Cheers,
Steve K7LXC
TOWER TECH
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