I've noted a bit of confustion on the effectiveness of torque bars.
First, torque bars do work when rigidly installed.
Second they work without resorting to 6 point guys (2 per arm)
Third, they are more effective with the 6 point guy system than a 3 point.
For those who say they don't work all you have to do is the math.
When the arm moves it translates to linear pull on the guy. An 18 inch arm
is going to pull more on the guy than when the guy is anchored directly to
the tower leg. With Kevlar guys this is substantial force as there is so
little catenary and give in the guy line.
The big question is; Do you need them?
"My own opinion" is , It all depends. If the tower load is some long beams
I'd certainly use torque arms. If the antenna/wind load is minimal I'd not
bother.
On my system which is most likely not typical
http://www.rogerhalstead.com/ham_files/Tower29.htm and
http://www.rogerhalstead.com/ham_files/Tower26.htm I do use the torque arms
at the top. I do not use them at the middle and bottom levels.
The top guys are tensioned to a bit over 600# while the bottom two tiers are
about 450#
I've been up there in winds near 30 mph and the top of that tower does not
appear to move.
However, looking up through the antennas at the clouds when the wind is
blowing like that creates a tendency to leave fingerprints in the tower
legs.
Roger Halstead (K8RI, EN73 & ARRL Life Member)
N833R, World's Oldest Debonair (S# CD-2)
www.rogerhalstead.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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