[Towertalk] Rohn tip-over base failed

[Guy Olinger, K2AV]

You drill a 3/4 inch hole through the bottom of a Rohn 25 section and
you sure don't have much left over. It will just balloon worse when
you load it up.  Rohn 45 maybe you might get away with this, but not
25.

Dunno, it might even be that he's got some of that old stuff that
LOOKS like Rohn 25, which would be even worse.

Of worse import on reflection, the overload involved in this may have
done worse things elsewhere which are not as obvious. The whole
structure is due a very careful inspection.

73, Guy.

----- Original Message -----
From: "Lee Noonan" <vk2lee@maxnet.net.au>
To: <towertalk@contesting.com>
Sent: Monday, May 27, 2002 7:18 PM
Subject: Fw: [Towertalk] Rohn tip-over base failed


> Ford Peterson
>
> > There is NOTHING that can't be repaired ...Hi Hi...
> > Reinforced with steel plate and LARGER BOLT holes....
> > My tower isn't a ROHN but I used 3/4 bolts in the base of Mine. If
they
> can
> > be done up tight ..... they shouldn't wear... I haven't actually
seen the
> > base of a ROHN tower though...
> > 73
> > Lee VK2LEE
> > http://www.qsl.net/vk2lee
> > http://wwwqrz.com/vk2lee/
> >
> > ----- Original Message -----
> > From: "Guy Olinger, K2AV" <k2av@contesting.com>
> > To: "Ford Peterson" <ford@cmgate.com>; <Towertalk@contesting.com>
> > Sent: Tuesday, May 28, 2002 8:38 AM
> > Subject: Re: [Towertalk] Rohn tip-over base failed
> >
> >
> > > I wouldn't fix it. It's complained to you loud and clear about
the
> > > overload. I'd call it "weakened".
> > >
> > > 73, Guy.
> > >
> > > ----- Original Message -----
> > > From: "Ford Peterson" <ford@cmgate.com>
> > > To: <Towertalk@contesting.com>
> > > Sent: Monday, May 27, 2002 3:35 PM
> > > Subject: [Towertalk] Rohn tip-over base failed
> > >
> > >
> > > > A few weeks ago, my 68' tiltover tower failed in a huge wind
from a
> > > > microburst that came through.  One guy failed and the tower
was
> > > helpless
> > > > against 100+MPH winds.  I was disassembling the base section
today
> > > and
> > > > discovered something very interesting.
> > > >
> > > > For the last few years, I have been perplexed by the need to
forever
> > > be
> > > > tightening up the guys.  All the guys would loosen about the
same so
> > > the
> > > > conclusion I came to was that the base itself was sinking in
the
> > > moist loam
> > > > each spring.
> > > >
> > > > What I discovered today is that the tip-over base section
(Rohn's)
> > > had been
> > > > overloaded by the weight of the tilt-over with all the
hardware.  If
> > > you
> > > > have never seen the swivels on a tip-over base, they are
single 3/8"
> > > > diameter bolts pinned through the 25G type base section
tubing.  The
> > > whole
> > > > weight of the tower rests on a single set of 3/8" bolts.  The
holes
> > > in the
> > > > base section tubes were elongated downward by about 3/16" in
only a
> > > few
> > > > short years.  All three legs were worn about the same.
> > > >
> > > > I thought Towertalkians might want to know this so that you
can run
> > > out and
> > > > check your hinged base bolts.
> > > >
> > > > Now, on to how to fix this base so I can use it again...
> > > >
> > > > Ford-N0FP
> > > > ford@cmgate.com
> > > >
> > > > _______________________________________________
> > > > Towertalk mailing list
> > > > Towertalk@contesting.com
> > > > http://lists.contesting.com/mailman/listinfo/towertalk
> > > >
> > >
> > >
> > > _______________________________________________
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> >
>
>
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