[TowerTalk] Soldering Ground Connections

[Peter Chadwick]

Gary said:
>Solder will corrode in the ground or in the weather.
Solder will melt when high current goes through it long before the conductor
melts.<
May be true for 'soft' solder - tin/lead alloys, melting at around 230 deg C. Silver solder - 'hard' solder' -  is another matter, as it doesn't melt until its at red heat. As someone said, if your conductors get that hot through a current surge, they're way too small! Silver solder is pretty corrosion resistant too. The firebox and smokebox of a 5 inch gauge coal fired steam locomotive can't be described as being environmentally benign, and the silver solder seems to manage OK there without corroding.
Actual brazing of copper with 'spelter' is likely to be a bit dodgy, because you have to get it very hot and you can melt the copper. Bear in mind that strictly, 'brazing' and 'silver soldering' are different, although the terms get used loosely as being the same. Brazing actually uses finely divided brass (spelter) to provide the joining material, and, from memory, is heated until there is a puff of white smoke where some of the zinc boils out of the brass, and the spelter has melted. BTW, brass shouldn't be used in high temperature applications over a long period because it gets weakened by 'dezincification'. Not very applicable to ground rods.....
73
Peter G3RZP