At 01:01 PM 3/16/99 +0000, Pete Smith wrote:
>I plan to go over to totally non-conductive guys for the top set, and move
>my insulators down to the middle set. Question is, is Phillystran the only
>practical option? A few years ago, some guys in PVRC bought a large
>quantity of Polygon(?) fibreglass guy rod, which I understand is only about
>1/3 of the cost of Philly, but as I recall there were minimum quantity and
>handling issues. Can anyone enlighten me on this option?
Last year (summer 1998) I bought ten, 1000 foot, rolls of the Polygon 3/8"
fiberglass rod and we (Susan and I) have been slowly installing it on three
new towers over the past year. I paid $0.40/foot for it because I bought a
10,000 quanity. Lesser amounts cost more per foot and I don't remember
without digging out the files what it was.
PLP makes grips that attach to this size rod and even conducted a pull
tests for me. Many manufacturers produce fiberglass rod but only some are
aware of its use for guying and advertize it as such. Others, like Polygon,
are aware of this usage but guying is not a part of their sales pitch. The
rod is a combination of fiberglass, epoxy, and uv inhibiters that is
"pultruded" through dies to produce a product of a certain size (depending
on the dies).
If you search the internet, you will find many companies that makes
fiberglass rod with similar specs. The thing to watch for is the precise
measurements of the sizes and whether there is much deviation of size
during the pultruding process. You want to make sure that the grips won't
slip because you got a product that is too small due to deviation limits.
The Polygon product that I received had very good deviation control.
The rod comes rolled in 8 to 10 foot rolls. You need a team to unroll them
as one or two people might not be able to handle it. It has enough energy
to break teeth and maybe crack bones. The rolls want to become straight and
have to be carefully controlled. It wasn't that hard to unroll it but it
took at least three or four people here to do it smoothly.
It is best to unroll it soon (a few weeks max) after you receive it to make
sure no cracking or deformation occurs. If you have ordered 1000 foot rolls
then you need a 1000 foot long area to store it. And you should store it
where you won't run over it with a mower. That isn't good to do. Polygon
was willing to send me any length rolls that I wanted it in. I chose 1000
feet since I have the room to store it down a fence line here.
I have found it easy to cut the rod (I use a hacksaw) and to apply the PLP
grips. Standard 502 insulators are a good match for the grip loops. I
always have about 5 feet of steel cable at the tower end and about 25-30
feet at the anchor end with the fiberglass rod in between. This is to
prevent damage from possible falling objects on the tower and
groundfires/vandals on the anchor end.
So far the fiberglass rod is working out great for me. I know that W3LPL
has used the stuff for several years and may be able to comment on
long-term problems, if any.
73, Richard
k5na@texas.net
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