We just put up a 20' piece of chrome molly tubing for the Tampa Amateur
Radio Club last week. There are five antennas on it. A C-19, a 5 elem 6M
beam and long boom beams for 2M, 70Cm and 1.2Gz.
I can tell you that it moves around in a slight breeze . It hasn't been up
long enough for me to have had a good look at it in a stiff breeze but I
would expect it's going to move around a lot.
I was once told that what doesn't bend or flex breaks.
We also have a 25' piece of 3/8" wall chrome molly and when you pick up one
end of it there is quite a bit of bend in the middle of the tube.
As was mentioned earlier use the MARC program and run the numbers, if they
come out OK don't worry be happy.
Julio, W4HY
----- Original Message -----
From: "Tower (K8RI)" <tower@rogerhalstead.com>
To: <TOWERTALK@contesting.com>
Sent: Monday, November 22, 2004 11:58 PM
Subject: [TowerTalk] Chrome Molly tube.
> I'm looking for some chrome molly tube to replace the structural steel I'm
> using now.
>
> I currently have 2 22-23 foot long pieces of 1 1/2 inch with 1/4 inch wall
> butt welded together. Over the splice is a 24 foot length of 2" which
just
> nicely fits over the 1 1/2.
>
> This is on a 97 foot ROHN 45-G.
> There is a TH5 at 100 feet, mounted on the 2" pipe.
> At 115 feet there is a 7-L 6-meter C3i Yagi mounted on the 1 1/2 pipe
right
> at the top of the 2".
> At 130 feet is a pair of 12 L vertically polarized 2-meter yagis on a 14
> foot cross boom.
> There is a pair of 11 L vertically polarized 440 yagis inboard of the
> 2-meter yagis on the same boom.
>
> When the winds hit 50 to 70 MPH the thing looks like a blue gill fly rod
> that just tied into a Bass. I find it amazing the VHF and UHF antennas
have
> held together for two winters.
>
> My thoughts are the Chrome molly tube would be more rigid, albeit a whale
of
> a lot more expensive.
>
> Any thoughts? Socially acceptable suggestions?
>
> Thanks
>
> Roger Halstead (K8RI, EN73 & ARRL Life Member)
> N833R, World's Oldest Debonair (S# CD-2)
> www.rogerhalstead.com
>
>
> _______________________________________________
>
> 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.
>
> _______________________________________________
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> TowerTalk@contesting.com
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_______________________________________________
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.
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