[Elecraft] OT: Ladder Line Spacers

[David Dunn]

Here in VK land, the sun shines pretty well as much as anywhere I  think,
and with plenty UV radiation too.

the various "Poly" ropes commonly sold,  last only a few weeks when used as
halliards etc.    Nylon virtually lasts indefinitely  - ten years in my
experience and it still seems good.
Dacron is the same stuff as Terylene to the best of my knowledge
respectively USA/UK names.    I have experience with Terylene boat sails,
that seems to have a very long life.   Not sure of it's relation to Nylon,
but I suspect very close.

I also have some WW2 antenna guys,  made of I am sure some greenish colored
natural fibres  with a woven outer "tube" layer over the inner, these were
available surplus in the 60's in a Can  (opened by a tin opener!) Some have
been in use here for several years and although showing deterioration, are
still quite strong.

David VK3DBD




On Thu, May 13, 2010 at 9:03 AM, Tom W8JI <w8ji at w8ji.com> wrote:

> The dissipation factor of Nylon is about two orders of
> magnitude greater than polyethylene and the UV resistance is
> horrible.
>
> Wes N7Ws>>
>
> None of that may matter because the electric field strength
> in the insulator is probably low and almost all nylon has UV
> inhibitors now.
>
> The rope I use for antennas is nylon and it lasts a very
> long time in the Georgia sun.
>
> You have to look at the material characteristics of the
> particular nylon material for UV life, and the end
> application for dissipation factor problems. Even 100 times
> nothing might still be considered nothing.
>
> 73 Tom
>
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