In a message dated 4/20/01 1:19:24 PM Pacific Daylight Time, steve@oakcom.com
writes:
> Rotational stress will work harden aluminum more than you might
> guess.
You better believe it. Rotational torque will elongate any hole with a
bolt thru it. With an array your size, the aluminum mast will have a short
service life.
For anyone putting more than one antenna on a mast, one way to somewhat
minimize the total rotation torque is to stagger antennas on both sides of
the mast - i.e.. first antenna boom on the right, second antenna boom on the
left, etc. This will lower the total mast torque and stresses everywhere -
rotator, rotator plate, tower, guys, etc.
Anyone who doesn't believe this will work hasn't read the articles by
Dick Weber, K5IU, PE.
Cheers, Steve K7LXC
List Sponsor: ChampionRadio.com - Trylon self-supporting towers,
safety equipment, rigging gear, LOOS tension guages & more!
http://www.championradio.com
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