I've participated in two crane raisings of 120 ft and 130 ft of R45.
The 130 ft tower was assembled and guyed in 40 ft sections
which were raised individually. We used 3 slings, down through
the center, around a leg and back up through the center. This
allowed the 40 ft sections to hang perfectly straight. The guys
were coiled up and taped to each leg. This was in a tight space
next to a house right on the edge of a cliff with lots of trees.
The 120 ft tower was assembled and guyed in 30 ft sections.
The TOP (10 ft) section with mast, C31XR and F12 WARC 7
were preassembled on a short piece in the ground and raised
as an assembly. We had to be careful to align the elements
to fit around the crane boom when the top section was aligned
with the tower. A single heavy duty sling was used and the
climber had to pull each section vertical during assembly.
I recommend 3 slings. The guys were laid out in a straight
line from each 30 ft section. There was LOTS of room in
the cotton field :-). Total assembly time for the tower
and antennas was approximately 5 hours with 4 ground
workers.
I vote for a conservative 2 section lift on your 100 ft R55 tower.
Tom N4KG
________________________________________________________________
GET INTERNET ACCESS FROM JUNO!
Juno offers FREE or PREMIUM Internet access for less!
Join Juno today! For your FREE software, visit:
http://dl.www.juno.com/get/web/.
________________________________________________________________________
Where do you get ICE bandpass filters & beverage matching boxes? The
same place that pays for the hosting of this list: The eHam Store.
Order online at http://store.eham.net.
-----------------------------------------------------------------------
-----
FAQ on WWW: http://www.contesting.com/FAQ/towertalk
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
|