When the tower is designed free standing and the guying only for additional
safety I see no problem erecting the sections with a gin pole.
I did the same with my tower but the sections are only 10 feet.
We did that with three persons, two on the top and one on the ground and by
use of an electrical winch controlled from the top.
The gin pole for your task will be quite heavy so you need a helper up the
tower for sure to bring it up for the next section.
My tower bolts on the foundation are also 1", there are 4 on each leg.
You will see the tower on qrz.com, its 43" wide on the ground and 20" on the
top. The rotator is at 123 feet.
The foundation is about 150000 pounds.
[mailto:firstname.lastname@example.org] On Behalf Of Doug Ronald
Sent: Mittwoch, 18. Januar 2012 02:17
Subject: [TowerTalk] Safety of unguyed tower
Thanks for the responses I have so far:
>3200# of tower, held only with 1" bolts on 32" wide legs?
That's the info I was looking for. I'll be guying each section as
WA8JXM/N5SDO suggest with Synthetic Textiles' 7/16" braided rope with a
breaking strength of 2150 pounds. The only lateral loads are due to wind.
There are 48,600 pounds of concrete and steel in the foundation, so that
isn't going anywhere.
> Is this a commercial project or an amateur radio project?
Amateur - BTW, there is a picture of the 20' sections on QRZ now.
>Are the 80ft towers new?
> Has this design been approved by a licensed structural engineer?
Yes. The vendor is US Antenna Products and they have similar antennas all
over the world. They know what they are doing with the structural
engineering. I hired a PE, got county approval, and have already had an
inspection before the foundation and guy anchors were poured.
> If they say to use a crane then use the crane.
The problem with the crane is the length of a 70 ton crane. There are 3
hairpin turns to get to the site, not on my land, and the owners don't want
me changing anything. I knew this before purchasing the antenna, but the
vendor's installation manual allows for its erection via a gin pole and
winch - that is the route I intended to take only to find out that now in
2011 they don't support that method. I've had the antenna hanging around for
several years waiting for me to retire.
> How much experience do you have installing and climbing towers and
antennas of this magnitude?
Obviously zero, but I plan on coming up to speed without killing myself or
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