[Elecraft] DIY Hard-drawn copper wire

[kevinr at coho.net]

 From what I can find on the 'net, in my dad's metallurgy manuals, and a 
scan of my CRC the ductility of pure copper is 0.62.  A piece of copper 
wire which is thoroughly annealed will allow stretching of 62% before it 
fails at the ductile-brittle transition.  This transition point is 
temperature dependent so a warmer day is better.  Once you have 
stretched the copper you can stretch it again as long as you anneal it 
first.  I did not look up the annealing temperature of copper.

Thus, for safety's sake, stretch the line to a 50% increase or less to 
avoid having it part on you.  Copper alloys allow for less ductility so 
decrease the amount of stretching to avoid an accidental parting.
     GL,
          Kevin.  KD5ONS