Agreed that constructive help is best. Here is a quick sanity check on
the danger actually involved with the rigging as photographed. I've
taken down worse (after some temporary guying).
EHS and Philystran are rated at breaking strength 2100 to 4000#
depending on what is up there, not safe working load limits . What is
the safe WLL for "man-rated" applications? I don't know if there is a
spec but usual engineering practice would be to derate to 1/3 to 1/4 of
the breaking strength value. Will the tower fail if a guy breaks while
on it? Maybe? What if stressed with a gin pole lowering from a 2 way
guyed section?
The quick links for 3/8" which kinda look about what is there are rated
1400# WLL, but certainly aren't man-rated at that WLL. However, I'm not
aware of ANY ham tower guy hardware that is man rated such as links,
chain, hooks, etc are for overhead lifting and made from forged grade 70
to 100+ steel. Then there is the matter of how much more to derate the
Chinese made links sold at the local hardware store even though they
have WLL 1400# stamped on them.
Round links are available for overhead lifting, forged grade 80 of about
WLL 2500# for 3/8" but unlikely what I see in the photo. Plain vanilla
hardware again is rated 350 to 450# WLL for 1/4" rings. So these rings
are the weak points and as suggested earlier both rings and quick links
ought to be replaced with rated bow shackles with pins secured with
stainless steel safety wires.
The angle on his guys looks pretty good, better than spec, so maybe on a
nice calm day it would be reasonable to climb to make some
improvements. How did the LP get up there?
Grant KZ1W
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