I consider myself to be the poster child for Heights Towers. I visited them
towards the end of their stay south of Detroit. It happened to just be up
the road from my in-laws place. This was in the late 90's. I put up a
Heights 72 FT crank up in time for the last solar peak. Unfortunately, I
probably overloaded the tower and it came down in a brisk wind after only
being up for a month or two. See...some of us do try to stick to the old ham
radio credo about not having enough antennas up if it didn't come down last
winter.
There are several important things to remember. The designs they had were
prepared many years before and under different building standard
requirements. I had my proposed "tree" reviewed by an engineer who said the
vertical tubing of my lowest tier was inadequate. So I ordered the bottom
three sections made with the next size up, tubing. No problem for Heights to
do with the special fixture they use to set up for welding. They can use
almost any size tubing at almost any of their standard leg spacing.
My tower collapsed just above the bottom tier. I could not determine if it
was due to a weld failure, webbing or vertical tubing failure. Second
important thing: unlike steel, aluminum welds are not stronger than the
metal they join. I am not sure if I understood correctly that the welds may
be somewhat porous and that may make them subject to corrosion. I painted
all my sections with two-part automotive clear coat before putting it up.
Now, 8 years later, the remaining tower sections show no sign of corrosion
anywhere. I painted the welds twice. For Hawaii, that is saying something.
After discussions with Drake, he said he was having the designs reviewed and
updated. He did two things. All tower designs thereafter offered one-size
larger vertical tubing as the minimum size (extrapolated up the tower) plus
you could option one or two sizes beyond that. If I had optioned all my
tubing up one size I might not be writing this today. He also changed from
6061-T6 aluminum to 6063-T832. If memory serves it was cheaper, has the same
yield strength and you only suffer it being less shiny. It also comes in
different finished dimensions (being drawn versus extruded) than T6 so it
may not telescope well in some or all cases when mixed. That is probably one
main reason they don't offer replacement sections for old towers. They don't
carry the 6061-T6 and the designs are a little "weak" by today's standards.
My replacement tower sections had to be adapted when mixed with my original
bottom tier of T6.
If any of what I learned has remained true until today then he remains a
small operation. He may be having sections built in batches and thus not be
able to fill all orders on other people's schedules. His is a small family
operation (last I knew) and he stands behind his product. It is just that
there is not a high level of demand for his product and he doesn't have the
resources a larger company and sales would bring. Aluminum towers are much
more expensive than steel.
It may rain almost every day at my place. I have moss growing on the
concrete. I just figured an aluminum tower might outlast a steel one
(assuming it stays up in the air!). I wonder, now, if he has adapted his
towers for guyed installations. Certainly, the compression strength issues
they would create must be recognized. I can easily remove the pieces that
make this tower a crank-up, plus add adapter sections and make it a fixed
self supporting tower. I will certainly guy it, temporarily, if I spend much
time up top as I imagine the ride will be quite interesting (and perhaps
less safe than a steel tower).
I am not an engineer. Listen to any advice the manufacturer gives. Get the
advice of a good engineer and follow it. In my case, even that was not
enough. Hopefully, all of Heights subsequent customers benefit from my
experience and older ones will be more careful. I was lucky, my homeowner's
insurance adjuster turned out to be a former ham. If I had to do it all over
again I would design in additional margin as aluminum is less forgiving than
steel or change to a steel tower. I may yet do that.
Aloha, 73
Kimo Chun, KH7U
Message: 7
Date: Tue, 8 Apr 2008 19:22:38 -0500
From: "Bruce Jungwirth" <k0son@frontiernet.net>
Subject: [TowerTalk] Heights Towers
To: "Towertalk" <towertalk@contesting.com>
Message-ID: <003601c899d7$d3100540$96f1fea9@yourxhtr8hvc4p>
Content-Type: text/plain; charset="iso-8859-1"
Anyone out there have any experience with Heights Self Supporting Tapered
Towers ? If so, I'd like to here your opinion.
Bruce K0SON
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