Over the past 25 years, at 3 QTH's, I've used thousands of feet of the
synthetictextilesinc.com 1/4" and 5/16" and have been very happy with
it. Tough, strong, and lasts a very long time (MA winters, CA sun). I
do use 29/30mm ball bearing pulleys (blocks) from Harken HAR340,
RonstanRF20100 (20mm ok for 1/4" line), or Lewmar 29901341 ($15, best
deal) on the antenna hoist line and the support point has been an eye
bolt in/thru the tree, tower, or telephone pole. With plastic balls,
they never seize up and the reduction in friction and line wear is
huge. If the support line is over the branch it usually gets stuck from
pitch, the tree grows onto it, or it wears, so I don't use a branch as a
pulley. I use paracord as a pull down line on the insulator so the end
of the hoist rope can be retrieved when the antenna breaks w/o a tree or
tower climb. Of course any line will wear and fatigue over a pulley so
moving the line a foot or two every year or so helps.
ebay lines I've bought have been cheaters on diameter or not really
dacron/polyester. A tree climb is $100 each here, so I spend a few
bucks for something that lasts.
Grant KZ1W
Redmond, WA
On 9/2/2014 7:47 AM, Carl wrote:
Im going to be needing 500-1000' spools of polyester double braid rope
for supporting some more wire antennas in the harsh enviroment up
here. The 5/16" is rated at 3400 tensile and the wire will be about
50#. ID likely tension it to about 200-250# to reduce sag
Or would real Mil-C-5040H type III (550# ) or type IV (750#) paracord
be OK? Its certainly not as strong plus it stretches. That spec was
inactivated in 1997 and Ive been unable to find its replacement.
I only want to do this once as I aint gettin' no younger!
Carl
KM1H
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