> From: "W5PR" <W5PR@swbell.net>
> Subject: RE: Topband: Re-using Guy Grips
> Date: Mon, 26 Jun 2006 12:06:14 -0500
>
>
> Factory specs say that you can remove and reapply the grips twice -
> apply,
> remove, apply, remove, apply is the limit. If removal is necessary after a
> guy
> grip has been installed for a period longer than three months, it must be
> replaced."
>
> Chuck Dietz W5PR
>
>
I had a larger tower built with surplus Trylon 1678 sections. It was
erected with used guy assemblies. The guys were greatly overrated
for the job, being a mix of 3/8in galvanized and aluminum-clad;
also some 5/16in was used at the lowest of four guy levels.
Specs for a similar Rohn 45G tower called for only 1/4in diameter
guy cable. All the 3/8in cables used preforms. All the aluminum-
clad cables were assembled with *some* reuse of preforms at certain
points. The proper types were used, i.e. galvanized with galvanized
cable and aluminum with aluminum.
This ~16in face tower served me very well from winter 87-88 to
summer 2003 until a tree fell across one set of guys, bringing it to
the ground. I wince a little bit when I recall that some of the
aluminum preforms, which were reused, were missing *some* of the glue
and sand inside. I was careful to select those which had the most
material remaining. The galvanized preforms were all new.
FWIW there were no failures of any guy assembly components
anywhere from the tower down to the guy anchors in the ground.
The tower simply crumpled down and landed near its base. This is
precisely how I would want a tower to fail, if it must fail. It
was absolutely textbook. These aluminum preforms had been part of
a previous tower system that had been in service for some years.
If I had it to do over, I'd want to use all new preforms, but my
experience shows that I probably got away with this because of the
overrated guy assemblies. Even with, no doubt, extremely high
transient dynamic forces in the guys, these preforms held.
"Don't try this at home, kids".
73, David K3KY
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