FWIW, I selected an aluminum mast for my new tower installation. It's has
1/4" walls. It's made of the same stuff as my heavy-duty gin pole, which I
got from the same place (WB0W.) It was much less expensive than carbon steel
or chrome molly, and I was able share the truck freight with the gin pole.
But it's important to note that my 12' mast has 6' in the tower and 6' out,
with a 40-2CD (6 sq ft and 41 lbs) clamped to the mast about *six inches*
above the top thrust bearing. There's virtually no bending moment on the
mast. The boom strut attaches to the mast about two feet above the boom.
There's nothing above that. With this kind of installation, even somewhat
thinner wall aluminum tubing would probably do.
I wouldn't have used aluminum had there been any significant wind load more
than a couple of feet above the top of the tower.
73, Dick WC1M
> -----Original Message-----
> From: Pete Smith [mailto:n4zr@contesting.com]
> Sent: Thursday, January 04, 2007 8:00 AM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] Aluminum Masts
>
> Actually, if you look at the archive, there has been a lot of
> very good discussion about aluminum vs steel over the years;
> the big lesson I took away from that is that a lot of
> aluminum (wall thickness) is required to get the same
> strength as steel, which increases the cost, and that the
> mast will still be far more elastic than steel, which may or
> may not be an issue, depending on what you are doing.
>
> The search engine on contesting.com is an excellent way to
> search the archives back a long way.
>
> 73, Pete N4ZR
>
> At 07:48 AM 1/4/2007, nd8l@juno.com wrote:
> >I'm sure someone will let me know if I'm all wet ;-)
> >
> >--
> >Dave N0RQ
> >http://www.powerlinenoise.com
> >
> >-----------------------------------------------------
> >
> >On this reflector?? Don't count on it.
> >
> >:-)
> >
> >
> >
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