One comment about Steve's advice. As you get the tower plumb to the set
of guys you are working on, tension the guys to the ultimate tension
before going higher. Don't leave them loose or partially tensioned
thinking you will tension them later.
Also, I use a 48" level to determine plumb (assuming it is not a tapered
tower).
Gerry Smith, W6TER
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of K7LXC@aol.com
Sent: Wednesday, March 05, 2003 7:13 AM
To: k1my@msn.com; towertalk@contesting.com
Subject: Re: [TowerTalk] how vertical is vertical
In a message dated 3/4/03 3:29:12 PM Pacific Standard Time, k1my@msn.com
writes:
> It's 150' of R55. I'm in the process of plumbing before
> installing antennas. On a wind free day (infrequent here)
> a plumb bob from the top to ground level is just a bit
> less than 12" off indicating 89.6+ degrees vertical.
> Is this acceptable iaw std practice or rule of thumb?
> If not it's necessary to lengthen the guys at one anchor
> and that involves unwrapping guy grips as the turnbuckles
> are fully extended. This is my first experience with a
> properly engineered guyed tower.
>
First of all, this response is just going to Bruce who didn't
include
Preston's email address in his post. Please pass it along to him.
Dropping a plumbline is one way of doing it but I don't see it
typically
used in commercial tower construction. Using a transit is FB IF you've
got
one and IF you know how to use it.
The only thing you really have to worry about when building a tower
is
getting the tower plumb at the first set of guys. Take a little bubble
level
up to that point and see what it looks like. Have your ground guy take
in the
turnbuckle until that leg is plumb. Repeat for all three. Now the tower
is
plumb.
For the next section, all you have to do is sight up the tower face
from
the ground - you'll be able to see if it's in plumb or not pretty
easily.
Just adjust the turnbuckles appropriately and you're all set. Repeat as
many
times as necessary.
BTW if you're trying to use a plumbline in a wind, put the weight
part (I
use a big wrench or nut as you're just trying to put some tension on the
line) in a bucket of water - it'll dampen it down so that it will be
useful.
Cheers,
Steve K7LXC
TOWER TECH
_______________________________________________
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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