Date: Sat, 27 Aug 2016 19:26:47 -0400
From: "Roger (K8RI) on TT" <K8RI-on-TowerTalk@tm.net>
To: "towertalk@contesting.com" <towertalk@contesting.com>
Subject: [TowerTalk] Strength of installation raising cable for the
LM470?
When installing the LM470 using the raising fixture, the retracted tower
is raised from horizontal to vertical. The cable attaches to the tower
roughly half way out presenting one whale of an initial load on the
cable and winch.
K8RI
## On the UST towers, the cable attaches to the tower, ALMOST to the TOP of
the very bottom section. Galvanized .25 inch winch cable is rated for 5700 bs.
.25 inch SS cable is rated at one helluva lot less. .25 inch galvanized
aircraft cable
is rated at 7000 lbs bs. Although galvanized winch cable looks identical to
aircraft
cable, the BS ratings are vastly different. .3125 or .375 aircraft cable is
even stronger
of course. 2-4 pulleys will take the stress off of any cable used.
## UST welds a small rectangular steel plate to one tower leg, with a hole in
it. Welded
on all 4 x sides. IMO, it would be nuts to terminate the cable only 1/2 way
along the
bottom section. You might want to re think what they have done, esp if
laying the
tower over, with a mast, rotor, ant on top.
Jim VE7RF
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