At 09:33 AM 7/4/2005, Jim Jarvis wrote:
>The squirrel discussion reminded me that I need to buy another
>500' spool of rope to hoist wire antennas.
>
>The last one I bought came from rope-rope, no longer in business.
>It's .250" braided dacron, which has withstood major loads, both
>here and in VT. It's olive drab, and tends to disappear from view.
>
>Someone mentioned Cable Experts as possible vendors. I know that
>radio works sells some 3/16" od dacron, but I don't know how abrasion
>resistant it is.
>
>Would appreciate opinions about products and vendors.
During FD, we were stringing a 40m dipole in the trees, and discovered that
black lacing cord works really well. It's smooth so it slides through the
pine needles and bark nicely. It's black so it's invisible. I don't know
about longevity, but I suspect it's fairly UV resistant, and it's almost
certainly fungus and mold resistant. I think it's somewhere around 75 lb
test. I suspect it comes in both nylon (stretchy) and dacron
(less-stretchy) forms.
One problem was that since it's not round, but flat, it has a very
interesting torsional vibrational mode that excites a transverse vibration
(think Tacoma Narrows Bridge).
http://www.ludlowtextiles.com/lcngcrd.htm
The Mil Spec is MIL-T43435B. The stuff commonly available is described as
Type 1, Size 3, Finish B. Seems to be about $20 for a 500 yd spool.
Probably a bit wimpy for permanent installation, but, it's great for
temporary installations (one of the cool aspects is that since it's waxed,
it stays on the spool til you pull it off.. no more rats nest of cordage in
the tool box).
Parachute cord is at: http://www.johnhowardcompany.com/Parachute_Cord.html
and appears to be somewhat stronger (hundreds of pounds). It's also often
of a kernmantle type construction (longitudinal fibers in the middle with a
braided jacket).
>n2ea
>jimjarvis@ieee.org
>
>_______________________________________________
>
>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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_______________________________________________
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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