For a Rohn 45 Foldover tower, the folding section weighs 100# and the Boom
Section weighs 165#. They are very heavy on a Rohn45 Gin Pole and in both
cases, the gin pole is only extended enough to raise the load to the
required height. The Rohn gin pole is not designed to take any appreciable
side loads.
In previous discussions with K6NA Glen Rattman, he puts the 20 foot mast in
the tower after the first two sections are built and does it by constructing
a second 30 foot tower clamped securely to the first tower and uses the
second tower to lift the mast, then tears that tower back down.
Handling big masts is very dangerous work and for an amateur, the crane is a
reasonably safe way to handle it if the tower is already built. Working
with a BENT 20 foot mast nearly always requires a crane to get it down.
-----Original Message-----
From: towertalk-admin@contesting.com
[mailto:towertalk-admin@contesting.com]On Behalf Of jljarvis
Sent: Thursday, July 11, 2002 9:08 AM
To: towertalk@contesting.com
Subject: [Towertalk] mast disaster avoidance
Folks:
This thread still seems to persist. Some comments are
and a question are in order:
N4KG recommended either placing the mast inside the
tower while at the 20-30' level, or using a crane.
He further suggested a longer than normal ginpole.
Placing a 100lb 20+ ft mast inside a 130' tower was
"The SCARIEST thing" he'd ever done. I was only at
60', but I'd never do it again.
K7NI points out that the Rohn 25/45 ginpole rating is for a 70lb
section of 45G, so you're pushing it with a much heavier mast.
The root problem is balance and leverage, and lifting height, and it's
flat-out dangerous to pursue this with the top section in place.
If renting a crane isn't in your budget, REMOVE THE TOP SECTION OF
THE TOWER.
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