Hiya, TowerTalkians --
Several weeks ago I asked if anyone had lifted 100' of 45G in one piece;
I was going to put up 100' of 45G and a MonstIR on top and wanted to see if we
could save a bunch of time by installing it in one piece with a crane. I got
some good feedback on the feasibility of the tower erection and proceeded with
that in mind. We sank one section in the concrete so the lift was actually
90' of 45G and not 100'. We got all set up and the crane lifted it up a couple
of feet. There was 12 to 18 inches of deflection in the middle of the tower and
we decided that was acceptable, particularly since the first part of the lift
exerts the most stress on the tower, so we went for it. And it went up easily
and dropped into place with no problems. Hooray! We spent the next hour or
two installing the guys and then the MonstIR. This was the second MonstIR I've
installed with this crane operator so we had the system down and everything
went with no problem.
BTW these were real Radian/Rohn sections and they went together easily
with no problem. This was unlike my recent experience with Nello 45N that was a
real battle - I had to use two comealongs and a TowerJack on one section to
get it to pull down - yuck. :-(
Something I found out - hey, I don't know everything! - is that there is
a little tab welded towards the bottom of each section between 2 of the
braces. These are added when the first face is put into the welding jig during
manufacturing. The tower should be constructed so that these tabs line up on
the
same face. We did and it works. In some circles this would be a big DUH! but in
other cases it's a learning experience - hi!
I guess the moral of this story is that when it comes to a BIG antenna
like the MonstIR, using a crane makes it easy, safe, and fast.
Cheers,
Steve K7LXC
TOWER TECH -
Professional tower services for commercial and amateur
Cell: 206-890-4188
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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