That should work, but I agree you would need a 2nd person to pull the fish
scale. But it would have to be calibrated against a known tension for the
specific type of guy wire being measured. That's why a new calibration chart
must be made up when using the Loos gauge with EHS. The readings won't be the
same with EHS as with the same diameter 19-strand wire rope the Loos was
intended for, because the stiffness of the cable is a factor when the two fixed
points are close together as is the case of the Loos gauge. Even at 40"
separation I suspect the stiffness of the cable would be a significant factor,
especially with larger diameter cables, so the 10-times multiplication rule
should first be verified with a known initial tension before proceeding with
your particular guy cable. YMMV.
You could get by without the calibration procedure described above, if you
know that the tensions of the guys are already close to correct and you are
only trying to get them exactly the same for each guy level. With a three-wire
guy system, when the cables are pulled to the recommended 10% of breaking
strength, all three guy cables at the same level should have he same tension
regardless; tightening one turnbuckle will increase the tension on all three
cables. The proper combination of turnbuckle settings is whatever keeps the
tower as close to perfectly straight as possible. If one of the turnbuckles is
adjusted too tight, it will pull the tower out of alignment and even with only
a couple of turns on one turnbuckle you will easily see the visible bend. If
you tighten one turnbuckle one turn, loosen another one one turn or loosen each
of the other two a half turn, always keeping the total turns count the same.
I calibrated my Loos by purchasing a few feet of the exact type of 3/16" wire
rope intended for sailboat rigging that the Loos was calibrated for at the
factory. I securely attached that to an equal length of scrap 3/16" EHS, using
cable clamps and a strain insulator (you don't want the cables to abruptly slip
apart under tension while you are standing in the line of fire), anchored the
ends between two small trees. I pulled tension on the line using a
ratchet-puller, plus a turnbuckle for fine adjustment between notches in the
ratchet-puller, everything securely fastened in place using scrap cable and
clamps. Using the ratchet puller and turnbuckle, I then adjusted the tension on
the wire rope (which by the laws of physics has to be identical to the tension
on the piece of EHS) to each figure listed on the factory calibration chart.
At each setting and reading, I then moved the Loos from the wire rope to the
EHS and re-measured the tension, noting the Loos reading on the E
HS at each known tension setting and thus made up my custom calibration chart.
Don k4kyv
________________________________________
> First my disclaimer, I've used this method while building barb wire fence
> to test the tension so as to get all the wires close to the same tension
> and I don't know why it wouldn't work for what you are doing, BUT I don't
> guarantee.
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