I have never had much luck with a plumb bob, even without wind problems,
which we usually have here.
If you want to do it right, rent two transits and set them up 90 degrees
from each other at equal distances from the tower. Level them with their
internal bubble levels, then "pan" the instrument's view up and down the
tower legs. You will soon see that "eyeball" is often off a lot. Start at
the bottom guy point (hopefully before you install any sections above it)
and adjust the guys wires to have proper and equal tension ( rule of them
10-15% of breaking strength of the guy material) while at the same time
lining up the transit's reference line in the scope to be parallel with the
edge of the tower leg. The move up to the next guy point, etc. The
recheck everything once all sections are up. Sounds like overkill, but it
is the most accurate way I know of. An ounce of prevention is worth a
pound of cure, do it right the first time, yada yada yada.
73 John N5CQ
-----Original Message-----
From: Shane Dugas [SMTP:shane@eatel.net]
Sent: Sunday, June 20, 1999 3:56 AM
To: towertalk@contesting.com
Subject: [TowerTalk] leveling tower
I've started up with the tower and I've gotten to the second set of
guys. I was wodering if anyone has every had any luck with a plumb bob. I
don't have access to a transit so I've been climbing the tower with a level
and then making adjustments. It seems that eyeballing would be almost as
good as a plumb bob given a small breeze would tend to give a lot of
trouble.
Also, Is pulling to tower into plumb with the guys a common occurance. I
know rohn tower is pretty well made stuff I just don't have any
installation
experience so I'm not sure if variences between sections is as much to
cause
the tower to "wiggle" as it goes up. I started very level on the first
section and it didn't take long to get out ( a couple of sections)
Thoughts anyone?
KK5LC
Shane Dugas
Prairieville, LA
Shane@eatel.net
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