Herb, the typical "safe working load" of a rope is on the order of
10% of it's breaking strength.
I'd be looking at 1/2" or 5/16" double braided Dacron for a haul rope.
Buy twice the length you need plus 10-20% to allow for pulleys
or snatch blocks etc.
73,
J.P. W2XX
----- Original Message -----
From: "Herbert Sweet" <k2gbh@arrl.net>
To: <towertalk@contesting.com>
Sent: Monday, May 27, 2002 8:13 PM
Subject: [Towertalk] Tower Safety
> Our club (Poughkeepsie ARC) needs to replace its aging rope that is used
for guying and pulling up
> towers. We put up three 40 ft Rohn towers, each with its own beam. The
beams are 3 element 20
> meters, 3 element 15 meters, and 5 element 10 meters.
>
> Some time ago I calculated the maximum stress on the pull up rope,
probably at about a 20 degree
> angle, as being in the neighborhood of 350 pounds. We use a battery
powered windless to do the
> lifting.
>
> We have been looking at the black dacron that is supplied by several of
the ham supplies companies.
> It comes in 3/16 770 lb breaking strength, 5/16 1250 lbs, and 7/17 2150
lbs. Are any of these
> suitable? If not, what would you recommend?
>
>
>
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