I use 1/2" Dacron rope in pine trees and use weights as a tensioner as
G8JNJ illustrates here:
http://g8jnj.webs.com/Multi%20antenna%20configs(s).gif
I use 10 - 15 pounds of weight - a gallon milk jug or empty bleach bottle
filled with concrete and an bolt eye in the top works fine for me.
The object of the tensioner is to keep the support line in the tree static
- no rubbing on the tree. As wind flexes the trees, the weight bobs up and
down and moves through a (marine grade, properly sized) block that is tied
to the end of the rope in the tree and has a freely moving piece of line
connected to the weight and the antenna end.
If this doesn't last 5 years, you're likely not allowing enough travel in
the line through the block or your weight is too light. The weights at each
end of the antenna (I use multiple weights for loops) should never contact
the block and should be heavy enough to keep tension in the antenna, so to
allow 15-20' of travel isn't too much.
I have a 570' giant loop that has been up for years and through hurricane
force winds in this arrangement.
All else fails, you could have heavier supports installed in the trees with
rope or chain wrapped with neoprene sheets by a tree guy. Many of them have
done this, it is more common than you might imagine.
Wire will saw through the tree. Use the pulley arrangement in either case.
73,
Mickey N4MB
Mickey Baker, N4MB
Palm Beach Gardens
*“Tell me, and I will listen. Show me, and I will understand. Involve me,
and I will learn.” *Teton Lakota, American Indian Saying.
On Thu, Feb 16, 2017 at 6:59 AM, NC3Z Gary <nc3z@outlook.com> wrote:
> Thanks for all the replies, there are a few that give me some good ideas.
>
> I did not note it in my original post but I am using pulleys and Antenna
> Tensioner devices. The rope is not breaking due to tree sway. Between
> the trunk and the outside perimeter of the tree, the rope travels
> through and there are branches that the rope passes by, these branches
> move in the wind and rub against the rope.
>
> But either steel cable of some sort for this area, or some sort of
> flexible tubing slid over the rope in this area I see as solutions.
> Simple enough but I was over thinking the issue and didn't consider the
> simpler solutions. Thanks for the useful replies.
>
>
> Gary Mitchelson
> NC3Z/4 Pamlico County, NC FM15
>
> On 15-Feb-17 22:46, Grant Saviers wrote:
> If you shoot the
> > line into the limb crotch and keep the line close to the trunk it's not
> > clear to me what the source is for the abrasion.
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