Date: Thu, 6 May 2010 21:05:31 -0700
From: "Mike" <noddy1211@sbcglobal.net>
Subject: Re: [TowerTalk] My 48' Delhi Self Supporter folded over :-(
lost its bolts!
Mike,
It almost sounds like they were not tightened down to the correct torque to
begin with because they should not have come loose with lock washers. I
would get new nuts, bolts and lock washers and torque them correctly and
double nut the bolts.
Mike, K6BR
## I installed 22 x of those tower's in yrs gone by.. and never seen one
of em do what you had happen. There are doz's of em here on Vancouver island.
They are not my 1st choice for a tower. I currently have the 96' trylon.. and
those bolts
are super tight.. and that was 10 yrs ago.. and re-checked 15 mins ago. [excuse
to try out my new 2' long torque wrench.]
## You may well have defective bolts. You should also check the bolts on all
the
upper sections. Did you use the correct base stubs [ the stubs that get
embedded
into the concrete] ?? Every delhi I ever saw, including new ones, has 3
[THREE] bolts
per leg on the base stubs.
## Don't ever put loctite on galvanized bolts, you will screw em up. All that's
required
is one bolt, one flatwasher, one split ring lockwasher, one nut. I think the
Delhi uses 3 x
1/2" G-5 bolts for the stubs.. and also the 1st few sections.. then down
to TWO 1/2"
bolts per leg. IF you double nut them, then the bolts have to be way longer.
They make
special nuts for this purpose, thinner than a regular nut, called a pal nut,
or jam nut.
## I'd call this an anomoly... All galvanized nuts are slightly bigger, to
handle the mating,
galvanized bolts. I suspect you may have had defective nuts. Does delhi use
galvanized bolts
on the upper sections.. or electroplated hardware... like trylon ?
later... Jim VE7RF
-----Original Message-----
Hi Guys,
Mike VE9AA here.
My 48' Delhi Self Supporter folded over a couple days ago .....
As far as I can tell, the reason this happened is 2 large bolts (with lock
washers) backed themselves out and there were only 2 remaining legs holding
it up. We had some wicked wind up here on the hill the other night, and
poof, it's was over.
Has anyone else heard tell of this happening to any other Delhi towers? (or
'similar' self supporting flat-stock towers like a Titan, etc.)
After the fact, I heard that VE1DX had the exact same thing happen to him.
http://www.ve1dx.net/fall_down.html
What can I do to prevent this in the future please? Red Loctite? Tighten
bolts yearly? Other?
73/TNX, Mike VE9AA
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