In a message dated 3/4/03 3:29:12 PM Pacific Standard Time, email@example.com
> 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
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.