I've used automobile scissors jacks (old GM and Datsun/Nissan ones, for
example) to realign the ends of Rohn 25 and 45 sections. "Buffer" the
jack-leg interface with short pieces of 2 x 4. I've done many realignments
with the sections lying on the ground and also with them up in the air.
Getting them to nest properly while they're still on the ground is probably
a little easier and has the advantage of not requiring you to hoist the jack
up the tower, but either way works. If you do it on the ground, however,
make sure you actually nest the two sections that you're planning on
connecting, and *mark* one of the three mating legs of each section so you
know what goes with what once you get them up the tower. (When you spread
the ends of tower sections, you have no reason to believe the result is
going to be perfect equilateral triangles, so later rotation of one section
with respect to the other is to be avoided.)
I've never had to have a section re-welded; never even considered it, to
tell you the truth. BTW, I think TowerJack makes an alignment tool that
replaces the scissors jack.
If you do the work on the ground, make sure the insides of the upper section
legs and the outside of the lower section legs are absolutely clean and
devoid of dirt, gravel, etc., before you nest them.
There was a period some years ago when it seemed as though Rohn was totally
incapable of delivering new sections with unbent leg ends. But, then,
that's the stuff that leg ends are made of.....(Awwwww....)
Bud, W2RU
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Rob Frohne
Sent: Sunday, April 20, 2008 10:12 PM
To: towertalk@contesting.com
Subject: [TowerTalk] How to deal with bad fitting Rohn 45 sections?
Hi Gentlemen:
Thanks to Steve's good advice, I checked the alignment of the Rohn 45
sections I have and found that some sections are out of alignment by
almost 1/4". Some of this tower was left over from a project up in
Seattle, and I suspect that it may have been put aside as not well
fitting, but I'm not sure. I think N2EA mentioned a while back on this
list that he had to have a section cut apart and re-welded. I hope I
don't have to do that. I am tempted to try and bend the ends a little
with a jack or something to make things align, especially on one section
that looks a little bent already (in the wrong direction). What advice
do you have for me?
73,
Rob, KL7NA
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