[Towertalk] Tensile strength - Cu wire

Chuck Counselman ccc@space.mit.edu
Thu, 3 Oct 2002 18:11:17 -0400


I should have said explicitly that stranded *copper* wire lasts 
longer than solid *copper* wire of the same gauge.  Copper 
work-hardens to the point of getting brittle and finally cracking due 
to fatigue.  Stranded copper lasts longer because when it flexes, the 
maximum strain is smaller in a thinner strand.

"Copperweld" v. stranded "Copperweld" is a whole 'nuther story.

-Chuck, W1HIS

----------------------------------
1. In an antenna, stranded wire lasts longer than solid wire of the
same gauge.  Solid tends to fail by fatigue, due to the
stress-variation caused by wind etc.

2. It has been suggested that stranded antenna wire should be
insulated, and where insulation has been removed for
splicing/connections, the exposed parts should be sealed with
CoaxSeal, Liquid Electrical Tape, or whatever, to prevent corrosion,
because some RF current flows between adjoining strands.

73 de Chuck, W1HIS