In a message dated 99-03-08 11:45:20 EST, W4QA@charlotte.infi.net writes:
> What is the "proper" way to plumb a 100' guyed 45G tower? I have almost
> finished erecting the tower (it's up to 70' now) and have installed two
> guy stations at 33' and 66' (the last station will be at 99') using
> Phillystran with short 1/4" EHS sections down near the anchors. The
> tower is "plumb" according to my four foot level, but doesn't look that
> way to the eye. Not sure if its an optical illusion (due to the tower
> being in the woods with some really tall trees behind it) or not, but
> want to make sure its "dead on" accurate.
Hi, Rush --
I use a builder's level myself. On a 100' tower, you can be three
inches out at the top and still be within spec. I'd believe the level and
ignore your perception.
When you're up on the tower, just have your ground crew tighten the
appropriate turnbuckles until you've got it in plumb. You won't be able to get
all the legs exactly in plumb so get it close and you'll be okay.
The easiest thing to do is to get the bottom sections up to the first
set of guys on-the-money and then just sight up the tower for subsequent tower
segments. Then you can eyeball up the tower and be pretty accurate.
>
> Also, if I use the guys to pull the tower one way or another to
> straighten it up, doesn't this upset the balance of forces on the three
> legs? How much is too much when tensioning the guys to plumb?
>
When properly tensioned, the forces on each guy for that level should
be the same. Use just enough tension to get the tower in plumb and then
tighten each turnbuckle the same amount (3 turns, 4 turns, etc.) until you
reach the proper tension. Then everything will be equalized and plumb.
Since you have about a 1% chance of getting the proper tension on your
guys by "feel", I would suggest getting a Loos Guy Wire Tensioner to do it
right. They're available from Champion Radio Products - www.championradio.com
or 888-833-3104.
Cheers, Steve K7LXC
Champion Radio Products
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