I had a tree fall on guys to a 100' Rohn 25 tower about ten years ago.
Fortunately (?) I had installed only two clamps and they actually pulled
through (3/16 EHS). Couldn't believe it, but the tower stayed up and
straight! However, lesson learned was not to trust clamps ( I may have
saddled a dead horse on one of the clamps).
My lifelong friend and antena mentor, W0AIH, uses many nicro fittings and I
had some experience from years of rigging sailboats, so went with that for a
new Rohn 55 tower using 1/4" EHS. It was quick, cheap (if you don't have to
buy the squeezer), and has worked out very well. The fittings are about $1
each and you only need one per termination. It doesn't take long to get good
at it. I think John, W0UN ran some tests on these a few years back and found
a breaking strength very close to the rated 6000# for the 1/4" EHS. Up here
in northern MN, I have seen some grips come apart caused by ice sliding down
the guys. The little (end caps??) that come with the much more expensive
Rohn grips cure this, but the nicro press route just seemed like a good route
to go. My system with a big load is looking fine after several years having
survived some big storms that blew down 100 year old trees and damaged a
couple of my antennas.
Just another option.
John, N0IJ
Duluth, MN
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