> I just got one from Steve and it works fine for 1/4 inch EHS. The scale is
> included which goes down below 400#.....I have the smaller gauge from Loos.
>
> Jay
>
>
>
Hi Jay,
Thanx for the info on your Loos Tension Guage. I take it you have
the PT-1? I have the PT-2 which has the following calibration chart.
------------------------------------
SCALE | 3/16" | 7/32" | 1/4" |
-----------------------------------|
13 | 300/6% | | |
18 | 500/11%| | |
21 | 640/14%| | |
24 | 840/18%|500/8% | |
28 |1240/26%|740/12% | |
32 | |1060/17%| 780/9% |
34 | |1300/21%| 900/11%|
36 | |1680/27%|1100/13"|
38 | | |1300/16%|
40 | | |2000/24%|
------------------------------------
I have a really neat public domain program called DPLOTW. One
of its nifttier features is the ability to extrapolate, or
perform curve fitting. I entered the data points for all
3 cable sizes and using a log scale for the X-axis (pounds)
I get a fairly straight line for the 3/16" and 7/32" cable sizes.
The 1/4" scale still has a slight curve to it. Another
feature this program has is the ability to fit the curve
to the data using a 2nd order polynomial equation.
I now have an extrapolated curve that gives me values
for lower values of tension that do not appear on the Loos'
calibration scale. Using this graph I can read values to below
300#. The expanded scale is shown below:
------------------------------------
SCALE | 3/16" | 7/32" | 1/4" |
-----------------------------------|
13 | --- | | 315 |
18 | --- | | 385 |
21 | --- | | 438 |
24 | --- | --- | 500 |
28 | --- | --- | 615 |
32 | | --- | 780/9% |
34 | | --- | 900/11%|
36 | | --- |1100/13"|
38 | | |1300/16%|
40 | | |2000/24%|
------------------------------------
Some one on here performed a test to determine
how close the Loos Guage calibration scale is
to actual weight. They hung known weights off
a work bench and noted the actual -vs- shown
tension. The conclusion was that the Loos Guage
is accurate to within 2% to 8%. The actual tension
is 2% - 8% higher than shown.
Based on the above emperical data and the extrapolated
data I derived, a reading of 28 corresponds to a tension
between 627# and 664#. This is close enough to the
recommended tension of 650#, or 10% of the 6500# breaking
strength of 1/4" EHS. As long as all the guy wires are
at the same tension the small margin of error should be
negligible.
*****************************************************************
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* 73 de Walt Kornienko - K2WK (FRC) *
* *
* k2wk@crystal.palace.net or K2WK@N2ERH.NJ.NOAM *
* Snail: 52 Sunset Inn Rd Lafayette, NJ 07848 *
* 201-579-1966 (home) or 201-579-3660 (shack) *
* *
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