We read and learn. w0un and I are not in total agreement,
but he's a bright and reasonable guy...and it's obvious that
the problem is communications. We're describing the elephant
from different appendages.
I'm still looking for Weber's paper...but in the course of
googling it, I came up with a TT post on the SAME TOPIC, made
by me, in 2002. Did we ever resolve the question of windload
on a helix?
After I read Weber's paper, John and I will chat offline...if
any concensus develops to help the guy trying to balance the
kt34XA, one of us (not both) will post it.
THAT SAID.... I submit the following observations:
* Windload calculation and torque balancing are different problems.
* John is right, the elements for the most part cancel out. If you
place your hose clamps exactly the same way in all locations,
they pretty much DO cancel out.
* 45 degrees is the worst angle to calculate windload...and that
problem is truly gnarly...but you don't have to solve it to
"balance" the torque.
* Adding weight to the nose, instead of offsetting the boom is the
smartest idea I've seen so far. It may worsen the aerodynamic
imbalance, though.
* Even with weight added, the array isn't symmetrical, due to the
clean 10m director, and maybe 5% differences between reflector
and directors.
* The nose will need a trimtab. I used 4" x 8.5", 15' from the mast.
It could be slid, for tuning.
Best regards,
N2EA
jimjarvis@ieee.org
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