[TowerTalk] Brazing copperclad rods to #2

[Nick Pair]

There are several cravat's I can see to this process. 
  !. At the temperatures you need to braze you might burn through the individual strands of the AWG#2 stranded before you had the rod up to temp..
  2. You might need to wrap the wire around the rod to form one loop to get enough area to braze.
  3, You might end up burning the copperclad away from the brazed area.
  4. You might have trouble getting the filler rod on the bottom side of the joining area on driven rod while standing on your head in the hole to see whats happening and trying not to catch fire. Been there, done that.The eye brows don't take that long to regrow.
  Since you stated experience in this field you should be able to circumvent these pitfalls. 
  I too have never heard of silver content in brazing rod, as the silver would vaporize at brazing temperatures or at best have run off long before that temp. was reached. Some confusion with "silver" solder may have occurred.
  All the commercial/industrial spec's I have ever seen have called for Cadweld (TM Erico) or and type of crimped connection applied with a Hypress (TM) type crimpper (which will almost push the metals together and leaves the joint under compressive stress) and approved by U.L. for the application.
  Brazing rod is a combination of copper and tin and other metals to improve its wetting ability at temp. All connections under high current for copper and aluminum buss bars are heliarced with the base metal as filler.
  Remember flux removal after is very important to slow corrosion of joint. 
   
  Fire in the hole!!!
  Nick 
  WB7PEK
   
   

 		
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