Steve is right: AB-577 guys are 1/8" galvanized or stainless steel. That's
below spec for Rohn 25.
Further, the AB-577 guys are tensioned with "snubbers" which clamp the guy
wire. Not at all clear the snubber clamp or even the snubber body can stand
up the forces on a Rohn 25 tower if it's has any appreciable load on it.
Also, the tower end of the guys have relatively small clips to attach the
guys to the tower. I've had a couple of clips break, and was just lucky to
have noticed it before the mast came down in a strong wind. In one case, it
was a base guy so all I had to do was replace the clip and retension the
guy. In the other case, the broken clip was on one of the upper guys. Unlike
a Rohn 25 tower, I didn't have to climb up to fix it (not possible anyway.)
All I had to do was lower the mast. I'd be scared to death to climb a Rohn
25 tower to replace a broken guy clip at the top!
Also, AB-577 guys are designed for 50' and 75' 5" lightweight tubular masts.
In the case of the extended 75' version, the mast has an extra set of guys
(4 sets of three guys in all), and each set of two has its own guy anchor.
The anchor for the upper set is spaced 20' out from the lower set.
All that said, it wasn't clear to me whether the author of the post was
talking about using AB-577 guys for permanent guys or just for temporary
guys. If the latter, then I think it's OK if care is taken to properly
secure and tension the guys. In fact, I used AB-577 guys as temporary guys
when erecting my Rohn 55 tower. They worked pretty well for that, and I felt
they were certainly as safe or safer than plain rope. Besides, I only had
four sections to stack before putting on the first set of permanent guys,
and that much Rohn 55 supports itself pretty well with minimal guy tension.
However, had there been even a slight breeze, I wouldn't have attempted to
climb the tower or raise 100 lb sections. YMMV, and be careful -- I know of
at least two recent cases where hams were seriously injured when temporary
guys failed.
73, Dick WC1M
> -----Original Message-----
> From: K7LXC@aol.com [mailto:K7LXC@aol.com]
> Sent: Friday, April 10, 2009 4:59 PM
> To: towertalk@contesting.com; nekvtster@gmail.com
> Subject: Re: [TowerTalk] Guyed tower question
>
>
> In a message dated 4/10/2009 8:56:46 A.M. Pacific Daylight Time,
> towertalk-request@contesting.com writes:
>
> > I am putting up 80 ft of Rohn 25. I am using the steel guys that are
> part of
> the extension to the AB577 system. The benefit is they are one-piece,
> adjustable in length and available to me since I'm taking down my '577 in
> favor of the Rohn 25.
>
>
> > This is also my first tower installation. I am not comfortable
climbing
> above a point that is guyed.
>
>
> Then by all means install it correctly. I doubt that the AB577
> guys are 3/16" EHS as per the factory specs. Anything less is potentially
> disastrous.
>
> Cheers,
> Steve K7LXC
> TOWER TECH -
> Professional tower services for hams
> **************Feeling the pinch at the grocery store? Make dinner for $10
> or less. (http://food.aol.com/frugal-feasts?ncid=emlcntusfood00000001)
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