The discussion over failure modes prompts me to recall an incident that
happened some years ago with an E-Z Way tower.
I had obtained the tower as the second or third owner, and it had the
optional 'Magic Post" or somewhat similar name. It was removed from the
previous owners premises with a cut off saw just below the ground level.
The lower portion of the post was replaced with a heavier, larger diameter
post as well as replacing the four "fins" that were each of 1/8" x 4" stock
with 1/4" x 6" x 6' stock that made it look a bit like a V-2 rocket. The
replacement post section was sleeved over the original post. It took a lot
of manpower to carry this into the back yard. The design of this post meant
that no concrete was required. The hole was back filled and with water
tamped with a 4x4 every few inches. This process took several days. It was
rock solid until it was removed some years later. But I digress...
When manually cranking up the three section sixty footer, I began to notice
considerable resistance, about this time every section telescoped
instantly. I surmise that the Cushcraft A-3 elements could not follow quite
as quickly, so deflected in an upward motion, then when the tower bottomed
out they came down at an accelerating rate, snapped off and I was showered
with aluminum. Fortunately all that hit me were in a horizontal plane, and
there was no injury. The lifting cable was found to be shredded and off a
pulley, and caught on the "axle" of the pulley where it had doubtless
stretched until it failed.
Moral: If it doesn't feel right, it probably isn't.
Otherwise it was a good, solid tower, and is in service to this day.
However, two towers installed since then have been Rohn 45.
73,
K9PJ
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