In a message dated 8/8/2005 5:25:06 AM Pacific Daylight Time,
towertalk-request@contesting.com writes:
> Right, it's a measure of the force required to bend a wire
under a particular tension.
> So there are two components of the 'resistance': that caused
by the tension, and that caused by the wire stiffness.
> The wire stiffness remains constant. At low tensions, it
dominates. As the tension increases, becomes a smaller and
smaller percentage of the total. The question is what
percentage of the total at common (10%) pre-tensions?
> I don't own the Loos gauge, but gather that:
> 1) The supplied chart or table does not give alternate
calibrations for different guy material.
> 2) The chart is calibrated for flexible cable (wire rope).
> The larger gages I own have alternate calibrations, but
only for the overlapping guy size range (1/2" to 3/4")
where EHS is available in both 1x7 and 1x19 configurations.
> I would think it might be useful for someone to actually
calibrate the Loos for 3/16" EHS at 400 lbs, and 1/4" EHS
at 600 lbs, and take away any doubt. I may pick one up
from Champion and do it. I should have one of these in my
kit anyway.
As an unscientific test some years ago, I took several different 3/16"
guy materials - EHS, Phillystran, and good old 7x19 wire rope - and hooked them
all together in one length. Then I put the whole thing under 400 pounds
tension per a Dillon tensionometer and measured each segment. Guess what? They
all
measured 400 pounds on the Loos. And the accuracy vis-a-vis the Dillon was
within a couple of percent - highly accurate in my book.
And like Bud, W2RU, said, having them equalized - regardless of the
tension - is half the battle.
Cheers,
Steve K7LXC
TOWER TECH -
Professional tower services for commercial and amateur
Cell: 206-890-4188
_______________________________________________
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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