[TowerTalk] buying new tower

[S. J. Blackwell]

>>
>
> >With 2 bolts on every joint,
> >I just can't see how any noise could occur.
>
>After a very few folding operations I noticed that the bolt holes were
>becoming slightly elongated, particularly in the vicinity of the hinge, and
>the sections moved perhaps as much a 1/16 inch up and down as the wind blew
>the antenna.

Tod,
This is a striking finding. I had a 60 foot Universal aluminiun tower up for 
25+ years. It never behaved as you described. When I took it down, the base 
was unbolted and a large crane was used to lift it from its site from 6 feet 
behind my house. It was lifted from the back yard vertically over the two 
story house and laid down in the front yard. The bolts between the sections 
were removed and efforts were then made to take the sections apart. I found 
the sections to be frozen together as the similar metal interface had 
galled. One section was damaged and was discarded during thes efforts. No 
holes were elongated. I almost believe the thing would have stood at that 
point in time without the bolts. (don't worry I will not try this) It took 
tremendous force from a hydraulic jack to seperate the sections. I have put 
it up at another site with new lower sections (30" vice 26"). Again nothing 
like you describe. It has now been up about 4 years.(It was never folded 
over.)
   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. An aircraft that had wing spar bolt or 
rivet holes wallowed like that would have been junked.

73,
Sam, W5LU

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