I would agree with Tod. The "old" Heights specs were not as robust. I have
40 feet of "old" Heights and the wall thicknesses vary by cross-sectional
size, but are indeed substantially thinner than the "new" Heights. I had to
drill new bolt-holes in one section because of the elongations.
Interestingly, as far as I can tell from the specs on the Heights website,
much of the "old" and "new" will actually fit together. Eventually, I want
to go up 3 more sections, to 64 feet, using "new" Heights sections if I can
find some reasonably priced second-hand.
I know of one installation where "old" and "new" Heights sections are
successfully mated in a freestanding tower, which (as far as I know) all the
Heights towers are designed to be. I've seen lots of discussion...pro and
con...on the subject of guying freestanding towers here, and I have a set of
loose "peace of mind" guys on my tower... for the very reason you mention: I
believe it's possible I have too much stress on the old sections, even with
only about 7 sq ft up there, and there's no way I could be sure.
I do believe in K7LXC's law..."Always do what the manufacturer says"... but
sometimes with used stuff nobody seems to know what that is... or was.. and
the manufacturer just won't tell you. Like Heights... and I did ask them.
73, Jerry K3BZ
----- Original Message -----
From: "Tod Olson" <tod@k0to.us>
To: "'S. J. Blackwell'" <w5lu@hotmail.com>; <towertalk@contesting.com>
Sent: Tuesday, May 11, 2004 8:38 PM
Subject: RE: [TowerTalk] buying new tower
> I will not try to explain this, but one must wonder why the
>bolt holes were wallowed out. From my old days of making
>experimental aircraft, one has to wonder if the bolts were too
>small for the holes or if the was just not enough meat for the
>intended purpose.
It is my opinion (and only that) that the wall thickness of the tubes used
by Heights in 1972 (when the tower was fabricated) was insufficient for the
stress I placed on the tower sections. I believe that the wall thickness of
the tubing used today is much greater.
Tod, KØTO
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
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