I used 3/8" black rod manufactured by Polygon in Indiana.
I think someone on the TowerTalk reflector was just looking for others
interested in purchasing this product. Polygon has a 5000' minimum, but
they were willing to break it up and drop ship to different locations.
I'm using it on both of my towers. So far no problems at all and it seems
to be weathering OK.
The advantages of fiberglass over steel are fairly obvious: nonresonant,
light, high tensile strength.
The disadvantages are perhaps less obvious:
It's delicate:
UV does affect it over time. It's not jacketed like phillystran so it will
deteriorate the strength member over time. However, this doesnt seem to be
a big concern for 10 to 20 years and if you buy larger than you need by
calculation, you'll have a lot of room for deterioration before needing
replacement. 3/8" seems to be a good choice, giving lots of margin in
strength for any large ham installation and room for some deterioration
over time. It's available in all sorts of colors, but I chose black as it
seems to last longer than other colors when used in ropes etc.
It's a soft material and has very little lateral or compression strength.
You cannot store this material in a coil for a long period of time or even
a short period of time in heat or sunlight. It will delaminate and break
in short order and will be ruined. The polyester resin is very soft and
will not hold up to abrasion well. You cannot allow anything to get close
to rubbing on it (trees, wires, etc) or it will get damaged. If you get
it, it'll be in an 8 foot coil shipped by freight up to 1500' long,
(however 1500' only weighs 150 lbs)! You must uncoil it immediately and
lay it out in fairly straight runs with very gentle curves on the ground to
prevent cracks/breaks from forming over time. I dont think I'd use this
material in areas with sandstorms or anywhere near trees.
Other considerations:
-Wear gloves!
-You need at least 2 people to unroll it. Do this by rolling the coil
along the ground, being very careful to keep the coil under control and
together. You must do this on grass or other soft surface to prevent
scraping the rod. Again, it's a very soft material, so it will abraid very
easily. DANGER! DO NOT try to uncoil this material while it's laying flat
on the ground! Fiberglass rod has tremendous spring energy and it WILL
hurt you if you lose control of it. We had a local ham chip a tooth when
the end whipped around and hit him in the mouth.
-Use vibration dampners - PPL makes the Glasgrips for fiberglass rod and
they also make a plastic spiral vibration dampner that should be placed on
at least one end of each guy. Because the fiberglass rod is a smooth round
surface, it'll vibrate like crazy in the slightest breeze if you dont use
them. Be sure and use heavy duty thimbles with the grips.
-For cutting, put a couple wraps of tape on the cut mark to prevent
splitting and use a hacksaw with a fine tooth blade. It cuts quite easily.
DO NOT use wire cutters!
-It is recommended that you use traditional steel guys up to 20 feet above
ground level and then transition to the fiberglass so you dont have the
relatively delicate fiberglass down where it can get hit/cut, etc., and
also for fire damage considerations.
Bottom line:
It's wonderful stuff to use once you know how to use it, work with it, etc.
It is so much lighter than steel, with or without insulators, that ground
handling and installation is a pleasure. Cost is much cheaper than
Phillystrand and perhaps cheaper than steel if you are using a lot of
insulators.
However, it requires great care in handling and special installation
considerations.
Disclaimer: This information is worth exactly what you paid for it! It's
based on my personal experiences and I assume no liability for its content.
Ty K3MM
"John Pitts"
<w7rg@hotmail To: tgstewart@pepco.com
.com> cc:
Subject: Fiberglass Guy Rod
02/23/2001
07:41 PM
Hello Ty:
I read about your antenna system last fall on the WX0B site -
identical to my No. 2 tower (w/ KT34XA's) except for the guy cable.
I'm now preparing for a third tower installation, and was
thinking about the fiberglass guy rod you have used as an
alternative to Phillystran. I might like to try it on tower
No. 2 and No.3
Could you tell me please who is the manufacturer of this
material, and how to contact them?
Any other comments on your experience with the fiberglass rod
would be appreciated.
Thank you much.
John W7RG
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